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Ron NewfieldRon Newfield 

Without AVGARDISK, Windows won't boot!

Having established that when the AVG disk driver avgsrdisk.sys is installed, Windows 7 WEI fails consistently, I have found a much worse problem :-
If avgsrdisk.sys is removed, renamed or corrupted, then Windows will not boot at all, not even in safe mode!
You can't boot at all using any of the safe mode options, forcing a Windows re-install.
This is a very important issue for an anti-virus program - If something gets onto your system somehow and just renames avgsrdisk.sys, then your system becomes un-bootable.
The only way round this without a complete Windows re-install is to get into Dos mode via the Windows recovery disk (If you have one) and re-instate avgsrdisk.sys from a backup.
This is a serious security problem.
Best Answer chosen by Ron Newfield
Ron NewfieldRon Newfield
They are not going to fix this.
This was first reported over 6 months ago and they say they can't even reproduce the problem, despite many people reporting the same problem on various operating systems.
All they need to do is delete or rename avgsrdisk.sys and EVERY version of Windows will fail to load, even into safe mode.
If anyone is doing a complete re-install of Windows for any reason, then just delete or rename avgsrdisk.sys and see how far a reboot gets.
Report the failures to this thread and maybe they will get their engineers to look at it properly.

I am afraid that the ONLY fix for this is to do a complete re-install of Windows.

All Answers

BalasubramanianBalasubramanian (AVG) 
Hello Ron,

We would like to investigate and assist further on this matter.
May I ask how did you narrow down that the issue is due to  "AVGARDISK" file?
Have you installed the AVG Antivirus free or the paid version of AVG Internet Security?
Ron NewfieldRon Newfield
Having established that when the AVG disk driver avgardisk.sys is installed via AVG, Windows 7 WEI fails consistently, I temporarily disabled AVG and then ran WEI again - it still failed.

Rather than un-install AVG, I renamed the file c:\windows\system32\drivers\avgardisk.sys to avgardisk.old and rebooted - disaster!

The last message out of BIOS was "Loading Operating System", then a message saying something along the lines of "System halted due to serious error detected which may cause damage to the system, check newly installed drivers and/or check for viruses".

I then tried to boot into safe mode and after loading many drivers, it failed with the above 'system halted' message again.

I tried ALL safe mode options and they ALL failed as above.

To recover the situation, I had to boot from a Windows 7 Recovery CD, go into DOS mode, rename the file back to avgardisk.sys and the system then booted normally into normal and safe modes.

I have to say that to install a disk driver (avgardisk.sys) which is essential for Windows to boot from is potentially dangerous. There is no indication, nor documentation that states that an essential disk driver is installed if AVG is installed.

I would suggest that most people would not be able to recover from this, even if they had a Windows Recovery CD, because there is no indication in the boot failure that Windows can't boot due to a missing disk driver.
BalasubramanianBalasubramanian (AVG) 
Thank you for the information, Ron.
This is the first time we are hearing this kind of issue. However, we aren't sure how you confirm that the avgardisk.sys file is the reason behind this.
It seems that the computer was able to boot normally into normal and safe mode when you renamed the file back to avgardisk.sys.
Hence, we confirm that this avgardisk.sys file shouldn't be the reason. If the boot failure was due to AVG, then there should be definitely some indication that this part of AVG is causing the issue.
May I ask when did you install AVG Antivirus on your Windows 7 computer?
Ron NewfieldRon Newfield
It seems that the computer was able to boot normally into normal and safe mode when you renamed the file back to avgardisk.sys - Correct

Hence, we confirm that this avgardisk.sys file shouldn't be the reason. If the boot failure was due to AVG, then there should be definitely some indication that this part of AVG is causing the issue - The indication is that when avgardisk.sys is not found by the Windows boot process, then the system fails to boot. When avgardisk.sys is found in c:\windows\system32\drivers, then the system does boot.

May I ask when did you install AVG Antivirus on your Windows 7 computer? - When I found that Windows WEI didn't complete the disk tests with AVG installed. I uninstalled AVG and WEI ran successfully. I then downloaded and installed AVG from your website on 08/04/19 at 16:39. WEI then failed again, so I renamed avgardisk.sys to avgardisk.old at that point. The next reboot failed from then on.

So, with AVG installed, avgardisk.sys must be present in  c:\windows\system32\drivers for Windows to boot.

I suggest that you rename avgardisk.sys to avgardisk.old and see what happens - Have a Windows recovery CD handy!
Ron NewfieldRon Newfield
PS - AVG versions :-
Version: 19.3.3084 (build 19.3.4241.445)
UI Version; 1.0.156
Virus Definitions Version: 190409-8
Shankara MoorthyShankara Moorthy (Sitel)
Ho Ron,

Thank you for the details. I'm now going to forward all this information to our developers. Let them try to induce the issue and if there require any changes, it will be done. Thank you for reporting this.
Randall BurkeRandall Burke
I am experiencing the same problem reported by Ron Newfield.  A power outage caused my computer to shutdown hard.  When I restarted it, I received a BSOD, so I tried booting it into safe mode.  When safe mode reached avgArDisk.sys it blue screened.  Sysem Restore Point won't recover it either.
Dinesh KrishnanDinesh Krishnan (AVG)
Hi Randall,

We're sorry to know that, We've already reported this to the concerend team & they're currently investigating on it. Once we hear from them, we'll update this post.
Thank you for your understanding in advance!
Patrycja JurczykPatrycja Jurczyk
Guys, I have the same problem and it's not funny anymore. Do I really have to re-install Windows or you are able to help? I'm asking because there has been a month since you answered this post
Santhosh PannerselvamSanthosh Pannerselvam (AVG)
Patrycja, we are sorry to hear this.

Please mention the Operating System in your computer and also the version of your AVG AntiVirus.
Patrycja JurczykPatrycja Jurczyk
Windows 7 and I don't remember which version I have, because I don't have access to my PC
Shankara MoorthyShankara Moorthy (Sitel)

Hi everyone.

We tried to induce the issue reported and unfortunately, we couldn't see the same behavior. I would request you to update the AVG version to 19.5 and check if the issue appears again. 

I would also like to understand the purpose of renaming the file avgardisk.sys. Awaiting for your response. 

Sam BlethenSam Blethen
I have the exact same problem with Windows 10. Considering contacting my attorney.
Priyanga SekarPriyanga Sekar (Sitel)
Hi Sam, 

We are sorry to hear about the situation. Please be assured that we will do all that's necessary to have this issue taken care. 

Please do contact us from an individual post where we can validate your account details and help you further. Make a note of your case number (08406783) for reference.
Peter LindstromPeter Lindstrom
Just tried turning on my pc and it is stuck in Win7 "Starting Windows". Try in safe mode and I see it stalls at loading avgardisk.sys.
Sarath PriyanSarath Priyan (Sitel)
Hi Peter,

We'll certainly check on this.

May I ask from when are you experiencing this issue?

Have you tried rebooting your PC in safe mode with networking?

Please take a picture of the error message while loading to check further.

You can post the image here in your topic. Click on "Answer" & then click on the "Image" [mountain symbol] & follow the instructions. 
Kender KenderKender Kender
Tengo el mismo problema. Mi windows 7 no arranca. ☹
He probado de todo ya. Solo me queda formatear.
Dinesh KrishnanDinesh Krishnan (AVG)
Hi Kender,

The support available here is in English currently. You can make use of Google Translator to translate our message to your language.
If you require support via email in your language, you can raise a request through this link. Please let us know if you're using AVG Free Antivirus. 
Stephen HStephen H
Having the same problem since AVG installed an update yesterday. Unable to boot the computer in ANY mode. Computer fails to boot.

Can I get a copy of avgardisk.sys so I can manually installe it in the c:\windows\system32\driver folder. Hopefully a fresh copy of this file will resolve the issue.
Dinesh KrishnanDinesh Krishnan (AVG)
Hi Stephen,

We're glad to look into this & help you.
Would you be so kind to let us know the version of AVG that got updated?
Also, let us know if you receive any option to troubleshoot while booting. 
Stephen HStephen H
Sorry, the coomputer in question is one of a fleet that we have. The user just reported that he was prompted to update, which he did, and that's when everything collapsed.
It's a Windows 7 system.
None of the troubleshooting options on boot up are successful. (system restore, SFC, Safe Mode - any variant, Windows Repair etc.)
The only way I have access to the files on the PC is by booting from a boot CD. To be clear THIS IS NOT BOOTING THE PC.
Can I get a copy of avgardisk.sys so I can manually installe it in the c:\windows\system32\driver folder. Hopefully a fresh copy of this file will resolve the issue.
BalasubramanianBalasubramanian (AVG) 
Stephen, we would like to know how you are able to get access to the PC files using the boot CD?
Could you explain the process in steps?
Unfortunately, we will not be able to provide the particular "avgardisk.sys" file.
Stephen HStephen H
Stephen, we would like to know how you are able to get access to the PC files using the boot CD?

I use a CD with software on it caller Hiren's Boot CD PE.

If you can't profide the required avgardisk.sys file then the only alternative is to reinstall the computer O/S?

That's nuts. Where do I send the bill for the hours wasted?
BalasubramanianBalasubramanian (AVG) 
Stephen, we value the time that you spent for this issue.
We can check what else can be done from the boot CD that you use.
If not, reinstalling operating system will be the possible solution on this matter.
Could you let us know the options that you would get when you run Hiren's Boot CD?
Stephen HStephen H
Hiren's Boot CD allows me to access and browse the PC. I have read/write access to files/folders, so I can retrieve data etc. (which I have done). That's the reason I want avgardisk.sys file. I want to know if I install an new version over rhe old one, I can prove (for you all) that it is this file that is causing the issue.
Santhosh PannerselvamSanthosh Pannerselvam (AVG)
Thank you for informing about Hiren's Boot CD.

It is not advisable to install the old version of AVG over the new one.

Will it be possible to remove all the files and folders related to AVG and then check whether you are able to boot into Windows?
Stephen HStephen H
For the sake of the exercise, I'll give that a go. But I cannot uninstall. Only manually delete.
Stephen HStephen H
I've deleted c:\program files\AVG, c:\programfilesx86\AVG and everything c:\windows\system32\drivers\avg*.* Computer still won't boot.

Wasted enough time now. Just going to reinstall the OS.
Priyanga SekarPriyanga Sekar (Sitel)
Stephen, we are sorry for what had happened. 
Since you are able to browse, we request you to run AVG Clear and remover tools as mentioned here (https://support.avg.com/SupportArticleView?l=en&urlName=Uninstall-AVG-software-Clear-Remover&supportType=home) and check if you are able to boot your windows PC. If the issue persists, please reinstall windows operating system and verify the status.
Ron NewfieldRon Newfield
I can't believe that I first reported this on April 9, 2019 and support is still faffing about with this major issue.
All you need to do is go into windows explorer and delete avgsrdisk.sys. Try to re-boot your PC into any mode and see what happens - nothing. You will need to do a complete windows re-install.
Has support done this and what was the result?
I had to re-install a windows 8.1 system the other day, so I renamed avgsrdisk.sys to avgsrdisk.old and tried to re-boot into safe mode - it fails when it gets to avgsrdisk.sys loading.
Nearly 6 months to identify let alone fix a problem like this is shameful.
When I was technical support manager for IBM, I would have been sacked by now.
Priyanga SekarPriyanga Sekar (Sitel)
We realize this must be upsetting. We've also tried to induce the issue reported and unfortunately, we couldn't see the same behavior. Unfortunately, we aren't able to find the root cause of the issue.
We need more information on this error message. If it occurs again, please share the picture of the message in this post. Once we receive this, we will escalate the case to our next level of support.
Stephen HStephen H
Too late. I've started the reinstallation process of the O/s
Priyanga SekarPriyanga Sekar (Sitel)
Alright, Stephen. Please reinstall Operating system and AVG programs. Monitor the progress and keep us informed here about it.
Thank you.
Sam VinsSam Vins
Good day! I have the same problem in two different OS: Win7_32 and Win7_64. It happens 03.10.2019 after AVG antivirus was updated. Now it is impossible to run PC, BSOD comes with 7B error and continuously reboots. Safe mode gives nothing. Process stops when try to start avgardisk.sys. I have access to HDDs (from bootable USB device) and may send any file to you for check to solve this problem.
Sorry for my english.
AvinashAvinash (AVG) 
Hello Sam.
We're sorry for the inconvenience caused.
Did you reinstall Windows using the bootable USB device? I'd request to post your own query to send you instructions on how to collect necessary information to analyze this issue.
Ron NewfieldRon Newfield
They are not going to fix this.
This was first reported over 6 months ago and they say they can't even reproduce the problem, despite many people reporting the same problem on various operating systems.
All they need to do is delete or rename avgsrdisk.sys and EVERY version of Windows will fail to load, even into safe mode.
If anyone is doing a complete re-install of Windows for any reason, then just delete or rename avgsrdisk.sys and see how far a reboot gets.
Report the failures to this thread and maybe they will get their engineers to look at it properly.

I am afraid that the ONLY fix for this is to do a complete re-install of Windows.
This was selected as the best answer
Sam VinsSam Vins
Well, I know how to do it, but I hope to save installed programms, so to reinstal Windows for me is the last thing to do. I have files from c:\windows\system32\drivers\avg*.* from both system (Win7_32 and Win7_64) if you need it. And yes, you may send instructions to my e-mail or write it here.
Sam VinsSam Vins
Ron, if they can't help me to fix my OS, I have to be sure that situation not happens again, in other case how we can trust this product?
Sarath PriyanSarath Priyan (Sitel)
I apologize for the inconvenience, Sam.

We request to create a new post to get your account information and we can send an email instructions to collect AVG error logs.
George DoddsGeorge Dodds
I've got the same issue, win 7 32 bit, wont boot at all, safe mode cmd prompt fails at loading avgardisk.sys, usual windows repir tricks wont work, is there an actual fix for this apart from re installing the OS?
AvinashAvinash (AVG) 
George, sorry for the inconvenience caused.
Did you try system restore? If that too does not work, please use original Windows installation disc to access the advanced repair options.
Ron NewfieldRon Newfield
I sometimes think that I am living in a parellel universe to you 'experts' who seem to have some magical way to get into Windows to do a system restore when you have been told by many people on many platforms on many versions of Windows that when avgsrdisk.sys is not present, then you CANNOT GET INTO ANY MODE OF WINDOWS UNLESS YOU DO A COMPLETE RE-INSTALL.
I have to say that I don't think much of your engineers if they can't replicate this.
I shall make it simple for you - Listen carefully, I shall say this only wernse :-
1) Delete, move or rename avgsrdisk.sys.
2) Re-boot Windows.
3) Try to get into ANY mode of Windows.
Write back when you have done this.
BalasubramanianBalasubramanian (AVG) 
Ron, when this situation occurs, we usually suggest users to boot the computer into safe mode and uninstall AVG Antivirus/AVG Internet Security program. 
Once it is done, we will ask them to restart the computer and see whether it boots into normally and works perfectly. 
At times user will not be able to get into safe mode due to AVG process as you mentioned. 
If it was possible to get into windows, then we shall try the steps as you mentioned or simply uninstall the AVG program to check the status.
Safe mode is suggested when customer is not able to boot into their windows. 
Stefan FarrellyStefan Farrelly
I am having the same problem today. PC wont boot normally, just sits in windows logo.
Rebooted in safe mode and it gets as far as loading avgArDisk.sys then stops and hangs. As it wont complete booting in safe mode I cant revmoe avg so im stuck.
However, i disconnected my second hard disk and now it boots aok. So avgArDisk.sys is having problems talking to my 2nd disk preventing boot. Is it running some scan on it or something ?

I can see my second disk in the bios so its ok. once booted on single disk if I plug in my second disk and do scan for new HW in device manager I can see my second disk fine, its working and all data is there.

so what on earth is avgArDisk.sys doing at boot with my second disk to stop it booting normally AND not booting in safe mode ?  An update to AVG virus definitions did indeed happen yesterday which I think caused this. I dont know if the software also updated. I use the basic free version of Avg.

Sarath PriyanSarath Priyan (Sitel)
Hi Stefan,

This isn't the experience we wanted you to have with AVG.

We are checking with our higher level support about avgArDisk.sys. Once we receive an update, we will post it.

Thank you for your patience.
Daniel SchellDaniel Schell
Ditto! Same problem for me, Can't find a solution other than a full re-install on my raid drive. Kind of upsetting. Will be taking my free version of AVG off of my machine and reporting this issue to anyone who has AVG immediately. I have been working as a PC Tech for over 30 years and I have never seen anything as disgusting as this. It's bad enough you guys created this issue to begin with but your "solutions" up to this point make me question your knowledge of computers in general. Not impressed!
Mike SickingerMike Sickinger
Oh, forgot to mention, I used both the AVG Removal Tool AND AVG Clear, neither one worked.  So they can't even uninstall their own product!!  Yeah, wouldn't hold my breath for thier support to figure this out, however, it does have the aroma of a class action suit
Mike SickingerMike Sickinger
I shared Ron Newfield's frustration and being tech support for over 20 years I agree, sounds like they aren't going to do anything, maybe not because they don't want to but because they are incapable.  Can't get any easier than deleting a file and rebooting.  In any event, I ran into the same issue but I was a little better equiped to deal with it as I have Macrium Reflect backup with a boot sector to enable restoring my computer from regular disk image backups I do every night.  This allowed me to go one step further.  First let me say, the issues I'm encountering (same as Ron's) are happening after doing a complete uninstall of AVG; so yeah, not so complete.  Anyway I tried removing all registry entries thinking I would then be able to remove the dreaded avgArDisk.sys file without issue.  Good thought but as it turns out AVG has locked down their registry entries, even starting registry editor under "System" has no effect!!  Mind you, this is after I uninstalled the product!!  This is virus like behavior!!  So, I took it a step further;  I have several hard drives on my system, I set another one up with a clean install of windows 7 Professional, booted to it then used a remote registry editor to try and remove the left over AVG keys in my main system's registry, didn't work still got access denied  WTF  definitely virus like behavior.  Also ran into the same road blocks trying to delete  C:\%user%\appdata\local\avg folder also left behind by the uninstaller.  My advice to anyone with this problem, if you have to reinstall the OS, DO NOT reinstall AVG.  I went to Panda, so far so good.  I will figure this out because I have way to many applications to be reinstalling them all so I'll post back when I do.
Mike SickingerMike Sickinger
Ok Everyone, I figured it out :-)  when something acts like a virus you need to treat it like a virus.  In order to delete the dreded avgArDisk.sys file for good and leave your system bootable you must remove it's corresponding registry keys but you can't do it with registry editor you need the Malwarebytes tool  Regassassin (FREEWARE) you can download it here https://www.malwarebytes.com/regassassin/
This is a stand alone program meaning no install necessary just download the file and double click it.
Once you have the program open you need to copy and paste the following registry keys in one at a time and click delete, say ok to the warnings:

Now reboot, once the system comes back up you can safely delete the dreded avgArDisk.sys file without consequence. 

As noted in my previous post, I had already uninstalled AVG and used their removal and clear tool but still had remenance of the program including avgArDisk.sys.  What you may not know is that avgArDisk.sys isn't the only driver they install, here's a list of the others


I will be proceeding to remove them as well using the method described above, you'll have to find their keys first and a sweet piece of software to do that is Resplendent Registrar Lite, it has a nifty search function that brings back all occurrances of your search criteria so you can copy the keys from one window, it's free for home use.

Yep, no more AVG for me :-)  It's a virus folks
avgArDisk sys Upset No talk just fix pleaseavgArDisk sys Upset No talk just fix please

avgArDisk.sys has stopped my laptop from working properly. I have been coming back for days after repeatedly asking for help to remedy the problem with avgArDisk.sys

Hi there. 

5th December 2019

Windows updated today however nothing changes as regards me not being able to get  'on' my laptop as I have always done by entering my correct password and logging into Windows. 

Windows 7 Home Premium
Service Pack 1

HP G56 Notebook PC

Pentium (R) Dual-Core CPU T4500 @ 2.30GHz 2.29 GHz
RAM: 4.00GB 
64-bit Operating System

Please can someone reply as occasionally having access via Safe Mode every now and then because of avgArDisk.sys will not permit me to run any other modes, to fix the problem that is that same file avgArDisk.sys, is an irony that wore instantly thin when I lost proper access to my laptop. 

I have accidentally posted this matter as an answer on another thread. 

It had been days since avgArDisk.sys completely messed up me being able to use my laptop. 

In Safe Mode (and No other version of Safe Mode), after getting 'stuck' (hangs)  @ avgArDisk..sys for a while, the windows login in page appears. I can type in my password and it is recognised and allows me to login in Windows. 

I cannot do that on any Safe Mode option, ie networking etc because the system gets to avgArDisk.sys and just hangs then restarts. 

When the laptop starts normally and the Windows 7 login page appears and I put in my correct password it says the my User Interface does not recognise me. Nb: This self password is used in Safe Mode and allows me to login Windows 7 

This is a much reported problem since at least April 2019 here and before that in Windows forums.

I simply want to get proper access to my laptop before avgArDisk.sys changed all that. 

Please reply. 

I don't have a Windows 7 disk. Safe Mode in essence just let's me on. 

Please reply with a right and proper solution/patch for the commonly occurring error. 









Mike SickingerMike Sickinger
Did you not read the post before yours ?  It gives you the fix, since you can get in using safe mode then you can apply the fix.  If you cannot get in using safe mode with networking then you'll need to find another computer to download Regassassin (FREEWARE) you can download it here https://www.malwarebytes.com/regassassin/  This is a stand alone program meaning no install necessary just download the file and double click it then follow the instructions in the post before yours.
Dmitrij SilovDmitrij Silov
I got this same issue today (Windows 7, HP notebook).
how do I launch the Regassassin if my PC doesn't boot? 
Do I need to remove the HDD from my laptop, connect it to another computer and run Regassassin there?
Dmitrij SilovDmitrij Silov
By the way, this is how the issue looks when booting in safe mode. It just gets stuck at loading that avg file.
User-added image
Mike SickingerMike Sickinger
Dmitrij,   these drivers should not be loading in safe mode, very odd.  So, my next step would be to make note of the full path to each avg sys file shown then get a copy of a windows boot disk, boot from the disk and select repair then command prompt, navigate to the \windows\system32 directory with the following command  cd c:\windows\system32 then issue the following commands one at a time hitting enter after each line
del /f avgbuniv.sys
del /f avgbidsh.sys
del /f avgardisk.sys

reboot the computer remove the cd then start in safe mode again, this should allow you to boot into safe mode.
Mike SickingerMike Sickinger
In the alternative you could remove your hard drive from the laptop and hook it to another pc, then use that PC to delete the avg????.sys files if you don't have a windows boot disk
Mike SickingerMike Sickinger
running Regassassin from another pc won't remove the registry entries from your laptop hard drive since the registry hive files won't be loaded in windows.
avgArDisk sys Upset No talk just fix pleaseavgArDisk sys Upset No talk just fix please
Mike Sickinger,

You have probably heard me screaming over the last month plus. 

AVG have updated my laptop with a file made by them, avgArDisk.sys​​​​​​. This virus file has disabled my access to my laptop. 

I have spent a month plus chasing AVG to acknowledge, then rectify the situation. They have been lamentable in that regard, where they have send more time being beyond condescending in repeatedly mansplaining to silly, clueless & brainless little woman how to click reply to an email, over and over and over again. 

Anything to deflect from actually sending a fix / patch. 

I have done everything AVG ask, as THEY detail how to fix the fact that I cannot have access to my laptop. AVG would change its mind about instructions, give me instructions where the second part was what I should have done first!!! or they tell me to completely ignore the previous instructions to 'fix' things or the last time ask me to find a file that does not exist?!?!?!?!?!

I have laid out how bad AVG is and has been in this regard, laying out the facts that so obviously illustrate that.

Now AVG will not reply. This has got beyond ridiculous  So I have sent word to the ceo's of AVAST  and AVG. 

This file is in effect a virus, written by AVG  and which AVG refuse to correct it in or as patch/fix/update/etc of this much reported problematic virus. 


I have seen your remedy above however I do not have another laptop/computer. 

AVG made the viral code and so I am relentless in pursuing AVG to rectify their mess. AVG continue to obsfucate or just not reply as regards their AVG created virus, that has affected people and computers/laptops across the globe. 

I can't get hold of crucial data on my laptop now, I need to have right and proper access to my laptop. 

I cannot download anything onto my laptop (nor do I have extra laptop / computer). Any advice would be appreciated. Truly. If any file/folder deleting is required, so as not to exasperated the problem AVG has literally created, I wil cross check that with AVG for their OK to do so. Catch 22, if not then AVG would jump at the chance to blame me and not them. 
Peter BraunPeter Braun
Yesterday I got the same issue..
The Computer (WIN7) failed to start.
When trying to start in safe mode it stopped at Loaded: avgArdisk.sys.
On the command promt of the recovery CD id renamed all avg*.x files in c:\windows\system32
and subdirectories to bvg*.sys and  renamed the AVG-directory in Programs to BVG.
Then run system-restore.
Fortunately the computer startet again.
I had to reinstall AVG-free.
Please fix that issue.......

Peter BraunPeter Braun
..all avg*.sys..
Peter BraunPeter Braun
..CD I renamed..
Shawn EnglemanShawn Engleman (Avast)
Hello, my name is Shawn, and I am writing on behalf of the AVG senior support team. My sincere apologies for the delayed response.

asw/avgArDisk.sys is disk upper filter. If you delete this file from disk, the operating system won't be able to boot, until you remove service name from below referenced registry key:


Further instruction to remove referenced registry key is as follows:

1) WIN+R - type "regedit"
2) Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E967-E325-11CE-BFC1-08002BE10318}
3) Right click on "UpperFilters" and choose "Modify..."
4) Edit "Value data:" delete "aswArDisk" only (original should be "PartMgr aswArDisk" so modify it to "PartMgr")
5) Click "OK"
Ron NewfieldRon Newfield
And how do you do that if your PC can't even get into safe mode?

You are deliberately missing the point. Your company has written software which stops a PC from booting unless that software is present. That is the definition of a virus.
If a hacker, worm or whatever, deletes, renames, or corrupts this file, then that PC is effectively dead.

Here is a way to get this fixed - For everyone who is affected by this virus, gets together and files a class action against AVG/Avast, they will fix it very quickly.
In the meantime, it is now over 10 months since this problem was reported to them, which proves that they are deliberately not fixing this for whatever reason, or they are not competant to do so.
Either way, they should not be trusted, or allowed to continue to trade.
What else is this virus file doing that we don't know about? - It seems very suspicious to me.
Even Microsoft would not force you to load an operating system driver file which you had to run or the operating system would not start.

Blast social media with this problem and warn every user in the world of this virus-like file.
Ralph ImRalph Im
Great bit of info there "Shawn Engleman"  For people who are stuck at the endlest reboot or bsod screens ,  We can not  (1) WIN+R - type "regedit" As you would understand .
So The following  link combined with Shawn's edits to the registry may help some ,
wintips.org/how-to-edit-and-modify-registry-offline/ ,
No second pc needed . to perform edits , But you do need some medthod
of making a bootable USB/DVD/CD if choosing to use EG  (Hiren's Boot CD),
If you have a windows instalation disk/usb already you are good to go with method 1
on the link
Always backup your registry files before any edits are performed ,
You can do this from the windows instalation disk after selecting repair your computer
and selecting the command prompt, Google "copy file using command prompt"
of course you need some ware to copy your files to , A usb stick maby .
If using medthod 2 (Hiren's Boot CD) copying files is a breeze
But you need a method of making the USB/DVD/CD Boot disk
Time to call in those favors owed ( Friends ) ETC.

HKEY_LOCAL_MACHINE \SAM >  %windir%\system32\config\SAM
HKEY_LOCAL_MACHINE \SYSTEM > %windir%/system32/config/system
[HKEY_LOCAL_MACHINE \SOFTWARE > %windir%/system32/config/software
HKEY_USERS \.Default] > %windir%/system32/config/default
HKEY_CURRENT_USER > %userprofile%/ntuser.dat


Joan Ramon S.Joan Ramon S.
I've a customer with same problem and I've been trying to solve it for a long.
I've tryed the solution proposed by Shawn Engleman and it doesn't work either. I've even tried a mix of this solution with Mike Sickinger's by removing the keys recommended by his program, also without success.
Obviously not being able to load Windows in any way I resorted to editing the registry offline (using an installation DVD following one of the ways explained in wintips.org/how-to-edit-and-modify-registry-offline/).
I definitely surrender and will be forced to reinstall Windows.I am disappointed with AVG and will be warning all my customers to stop using it. :-(
AvinashAvinash (AVG) 
Hi Joan.
We understand the inconvenience caused and sorry for the disruption.
If you can edit the registry items mentioned by Shawn, you should be able to boot your PC in safe mode.
Or, please try system restore to an earlier date.
Evelyn HeapsEvelyn Heaps

This is BS. I try system restore and oh what a surprise, the problem comes from Avast. I can't restore because of the same problem. 

so right now I have no access to a laptop with a lot of important information and memories. Thanks for not checking out your updates well. You created a virus and crushed us all. 

Sarath PriyanSarath Priyan (Sitel)
Hi Evelyn,

We apologize for the experience.

I request you to contact Avast support regarding this for further assistance.

https://support.avast.com/contact/ (https://support.avast.com/en-us/contact/)
Jose MoisesJose Moises
Hi all. Same situation after a power-off problem. This worked for me:

1 - Start machine and press F8 to get windows startup options
2 - Choose "Repair your computer"
3 - Select language, and login with your usual user
4 - A "System Recovery Options" window appears. Select "Command prompt"
5 - Run chkdsk c: /f   (in my case /r was not necessary, may be slow, but you cant try if first chance does not work)
6 - Wait to finish and see results.
7 - [OPTIONAL] Restart the computer, press F8 and this time select "Safe Mode". The machine will start normally bypassing the problem with the avgArdisk.sys
8 - Restart the computer, press F8 and this time select "Last Know Good Configuration (advanced)". The machine will start normally.
NOTE: The first logon after the repair may be slow, just wait 5-10 minutes.
NOTE2: chkdsk c: /f repairs the disk causing the boot problems. /r also repairs sectors but in my case was not necessary.
Astro JetsonAstro Jetson
Adding my name / history to the people that hate the useless techsupport people, Thanks "Shawn Engleman" for not having a clue that you can't regedit on a dead machine.   

"Sarath Priyan"  why not post the fix here, your tech support drones don't have a clue.   

Finally "Avinash", this problem has been around for almost 6 months, and that's about how long since my last reboot.  So your idea of "system restore" isn't going to work, since you borked the last system.  

I'll now spend an hour working on using a boot disk to see if I can fix this mess.  Nice job AVG, maybe change your motto from "Whatever your device, we've got a way to turn it into a brick"  

Tanyay ZoltánTanyay Zoltán
Dear All,

I'm facing the same problem, I will give a short description of my system installation:

Bootloader: Grub2, but all time, the mbr 446 bytes saved with dd, in every state, it means that i can restore a difrent OS bootloaders, any time, with Sysrescd Live spin.

ATTENTION: dd can destroy the whole data on your hdd, if you don not know how to use it.

(Remark: If you try to install Sp1 to Win7, you need it's own ntldr bootloader in mbr, with grub2 in mbr, you can not install sp1 to win7.)

My goal of installation should look like this:
/dev/sda1 (active boot flag) = fs type ext4 Centos 7
/dev/sda2 = fs type ntfs (drive c:\) - Windwos 7 x64 SP1
/dev/sda3 = fs type ntfs (drive d:\) - Windwos 7 x86

The problem is with /dev/sda3 - can not boot avgrdisk.sys, bricks the system.

Installation order:

1st sda2 Windwos 7 x64 - Devops workstation (AVG FREE installed)
2nd sda1 Centos 7 - I need linux, because it never fails, resistive to viruses ;)
3rd sda3 windows 7 x86 - Compatibility to old 32bit devices.

My installation technique is, I set active boot flag to sda3 and change partition type sda2 partition type to Hidden NTFS because this way the windows installer will not see the other windows system instance. I prefere to use Grub2 to manage the boot targets, instead of windows built in.

On sda3, at the end of the installation of win7 x86, the local user account created finally. After reboot the Windows 7 x86 on sda3 can not load avgrdisk.sys. Bricked.

Remeber: sda3 is ntfs + bootflag set, sda2 invisible fstype hidden ntfs.

What to do now?

I restored the Centos 7 boot record using Sysrescd live spin with the command "dd if=/path/to/mbr446.centos7 of=/dev/sda bs=446 count=1", set my active boot flag to sda1. Set sda2 fstype back to ntfs.

With this configuration: Centos 7 boot = OK!

Grub2 loads well Win7 x64 Sp1 with custom conf:

menuentry "Windwos 7x64" {
set root=(hd0,2) # First HDD, 2nd partition
chainloader +1

Win7 Sp1 x64 System is running and healty. OK!

Let's try to load the new install: Windows7 x86

menuentry "Windwos 7x86" {
set root=(hd0,3) # First HDD, 3rd partition
chainloader +1

Win7 Sp1 x64 booted instead of Win7 x86!!!

Cofiguration 100% -ok, My laptop uses the same boot configuration.

At this point, I decided to load back the MBR record of win7 x86 and set sda3 bootflag active, set sda2 to hidden ntfs (revert back to post installation partition schema of Win7 x86).

I can not figure out why Bricked on loading avgrdisk.sys after succesfully avgbuniv.sys and avgbidsh.sys was loaded to the system.

But wait a minute, How it possible that a fresh install of Win7 x86 (never logged into the desktop) loading succesfully avgbuniv.sys and avgbidsh.sys while the other Windows7x64 on sda2 filesystem is set to hidden ntfs.

After checking with Centos7 the avgbuniv.sys and avgbidsh.sys not exist on sda3 (Win7 x86).

I uninstalled AVG Free from Win7 x64 while MBR was also restored to it's own ntldr, still unable to boot Win7 x86. No success.

What should i do? Should I reinit the whole HDD with /dev/zero? I'm very upset.

My Question is: During AVG install, where are avgbuniv.sys and avgbidsh.sys registered to?

p.s.: I use a free version of avg, as i see this topic is older than one year, probably my solution is to add another HDD to the workstation, and boot with grub2.

But this solution is like the same as your car's engine failed, nobody can repair, so the solution is to buy another car?!

The real solution should be try to look another repairmen or service station, how knows the know how, how to repair.

Sincerely waiting to your kindly solution.

The world would be much better with Unix systems... and i wasted 5 hours to investigate this matter, instead of working on my k8s threads. Now I'm going to look for an unused sata hdd in my basement.

Wish better luck.
AvinashAvinash (AVG) 
Hello Tanyay.
Did you attempt the steps provided by Shawn Engleman in his last post?
Please write your own post to get your account details and help you further.
Thor ProThor Pro
I managed to fix this issue by using the windows boot media, and using command prompt to replace the existing avgArDisk.sys file with another version from another PC I had.
That fixed the issue for me.
Rakshith RajkumarRakshith Rajkumar (AVG)

Thank you for letting this know.
I appreciate your time and effort in this issue.
Feel free to contact us if you have any queries related to AVG.
Free JohnnyFree Johnny
I'm having the exact same problem! Has anyone found a solution for this?? 
Santhosh PannerselvamSanthosh Pannerselvam (AVG)
Hello Johnny,

We will help you to sort out the issue.

Please write your own post to get your account details and help you further.
Free JohnnyFree Johnny
Hi Santhosh. Since this thread explains exactly what my problem is, why not just answer here? 
Santhosh PannerselvamSanthosh Pannerselvam (AVG)
Johnny, we did ask you to contact us through a separate post in order to locate your account.

Once we located your account, we can provide you our additional support based the issue.

Thank you.
Hello everyone,

Don't reinstall your Windows before trying this out. It worked for me so it might work for you too.

Please watch this youtube video https://youtu.be/UGkLxry9_Gs

My Windows laptop used to hang while trying to load the file avgardisk.sys.

I tried everything...... Normal boot, safe mode, repair option, system restore option. None of them worked. Finally I found this video and followed the steps.

I copied the avgardisk.sys file from c:\program files\AVG\ ==> to ==> c:\windows\system32\drivers. Rebooted my laptop and it booted straight into windows.
Before you can copy the file, you need to first gain access to the computer's file system. You can use one of the following methods

1) Boot using a Windows Boot CD and open a Command Prompt to copy the file over
2) (or) Boot into Minimal Windows XP using Hiren Boot CD and use the Windows Explorer
3) (or) remove the HDD and connect it to an external HDD enclosure and plug it into a USB port

There are lot more ways to mount your HDD and gain access to the filesystem. Please give them a try. Let reinstalling Windows be the last option unless you don't have much to loose
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