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Mike SkyMike Sky 

Email Shield having issue with Thunderbird 78.2.2

Today I started having the problem of not being able to send or receive emails through Thunderbird (78.2.2­). When I tried to send emails I get the following message:
============================
Sending of the message failed.
Peer’s certificate has an invalid signature.
The configuration related to smtp.aol.com must be corrected.

==============================
I disable the Email Shield, then all was OK…I could send and receive emails.
I uninstalled AVG and reinstalled a fresh copy. However with the email shield enabled I still could not send or receive (same error message).
When the problem started, nothing had changed about Thunderbird or AVG…they were both working fine one minute and next minute I could not send or receive.
Any help will be greatly appreciated.
 
Best Answer chosen by Mike Sky
Rakshith RajkumarRakshith Rajkumar (AVG)
Hi Mike,

We will help you in this.
The AVG Email Shield uses an advanced scanning method for incoming and outgoing emails over SSL/TLS secured connections.
Mozilla Thunderbird have it's own certificate stores and may require extra configuration to avoid warnings about invalid Email server certificates.

Kindly refer this article for the troubleshooting :
https://support.avg.com/SupportArticleView?urlname=AVG-Troubleshoot-invalid-email-certificate

All Answers

Rakshith RajkumarRakshith Rajkumar (AVG)
Hi Mike,

We will help you in this.
The AVG Email Shield uses an advanced scanning method for incoming and outgoing emails over SSL/TLS secured connections.
Mozilla Thunderbird have it's own certificate stores and may require extra configuration to avoid warnings about invalid Email server certificates.

Kindly refer this article for the troubleshooting :
https://support.avg.com/SupportArticleView?urlname=AVG-Troubleshoot-invalid-email-certificate
This was selected as the best answer
Mike SkyMike Sky
Thanks very much…problem solved!
For your info…when I tried to import the Email Shield certificate into the Authorities Tab  (in Thunderbird’s  Certificate Manager), I got the message:
‘This certificate is already installed as a Certificate Authority.   Therefore it did not allow me to import it.'

However, then  I selected the AVG Web/mail Certificate  (on the same page – Authorities Tab) and clicked on ‘Edit Trust’

There I found that the box next to ‘Trust this CA to identify websites’ Was not ticked.
I ticked this box and then OK…

It all worked after that.

Thanks very much for your help.
 
Rakshith RajkumarRakshith Rajkumar (AVG)
You are welcome, Mike
I am glad that your issue has been resolved.
I appreciate your time and effort in this.
Please feel free to write back to us if you have any queries in the future.
We will be glad to help you.
TomTom SmithTomTom Smith
Hi!
I sseem to have the same problem - but I can't fiind help with the link above:
https://support.avg.com/SupportArticleView?urlname=AVG-Troubleshoot-invalid-email-certificate

Where can I find the article - what I can do to solve the issue?

Thanks!
Rakshith RajkumarRakshith Rajkumar (AVG)
Hi Tom, 

We understand your concern. In order to investigate this further, we require the error screenshot and your AVG account information.
Since you are not the author of this post, we don't have your account information.
Please write back to us in your own/new post so that we can access your account information and forward your concern to our higher level support.
Thank you for understanding.
 
Carlos UboCarlos Ubo

Hi, I have the same problem, aggravated by the fact that when I tried to import the certificate as instructer, Thunderbird tells me "This certificate is already installed as a certificate authority."
I tried to erase the certificate to reinstall it, but the process of deleting does not seem to work (I delete it, restart TB and the certificate is still there, so I cannot reinstall it)

 

Veeramani SivakumarVeeramani Sivakumar (Sitel)
Hello Carlos, 

We can really understand your concern. We request you to write back to us through own post. So, we will check your account and help you to resolve it. 

Thank you.
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