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live.mozillamessaging.com uses an invalid security certificate

  • 8 replies
  • 6 have this problem
  • 1 view
  • Last reply by Paul-H

Paul-H
Paul-H
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Every time I open Thunderbird I get the following warning

Secure connection failed

live.mozillamessaging.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. Error code: <a id="errorCode" title="SEC_ERROR_UNKNOWN_ISSUER">SEC_ERROR_UNKNOWN_ISSUER</a> 

  This could be a problem with the server's configuration, or it could be someone trying to impersonate the server.
  If you have connected to this server successfully in the past, the error may be temporary, and you can try again later.

I even get it on a new clean install machine so doubt its a virus/malware issue

Anyone got any thoughts as to why i get this error

Thanks

Every time I open Thunderbird I get the following warning Secure connection failed live.mozillamessaging.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. Error code: <a id="errorCode" title="SEC_ERROR_UNKNOWN_ISSUER">SEC_ERROR_UNKNOWN_ISSUER</a> This could be a problem with the server's configuration, or it could be someone trying to impersonate the server. If you have connected to this server successfully in the past, the error may be temporary, and you can try again later. I even get it on a new clean install machine so doubt its a virus/malware issue Anyone got any thoughts as to why i get this error Thanks

Chosen solution

The issuer DigiCert is legitimate. It's possible your Thunderbird certificate store got corrupted.

At the top right of the Thunderbird window, click the menu button , then select Help > Troubleshooting Information - Profile Folder - Open Folder

This will open your profile folder in Windows Explorer.

Close Thunderbird.

In Windows Explorer, look for a file cert8.db. Delete that file. It will be re-create when Thunderbird starts the next time.

Start Thunderbird. Do you still see the exception prompt?

Read this answer in context 👍 4

All Replies (8)

Matt
Matt
  • Moderator
  • Top 10 Contributor
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what anti virus are you using?

Paul-H
Paul-H Question owner
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I am using Windows Defender

Thanks

user1121639
user1121639
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See: https://support.mozilla.org/en-US/questions/993843

Their same issue was caused by "Browser Safeguard". Your issue may have a similar cause, that being something on your computer that is supposed to provide extra security for your web browser.

Paul-H
Paul-H Question owner
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Cant seem to find anything relating to Browser safe guard on my system.

Any idea where it might be hidden

Thanks

christ1
christ1
  • Top 25 Contributor
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Please attempt to add an exception on the bottom of the error page. Do not actually confirm the exception.

Then inspect the certificate - see the screenshot attached for instructions. Who is the issuer of the certificate?

Please post a screenshot of the certificate viewer window. https://support.mozilla.org/kb/how-do-i-create-screenshot-my-problem

Paul-H
Paul-H Question owner
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This is the result I get

https://support.cdn.mozilla.net/media/uploads/images/2017-01-15-08-38-12-44a50f.png

christ1
christ1
  • Top 25 Contributor
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Chosen Solution

The issuer DigiCert is legitimate. It's possible your Thunderbird certificate store got corrupted.

At the top right of the Thunderbird window, click the menu button , then select Help > Troubleshooting Information - Profile Folder - Open Folder

This will open your profile folder in Windows Explorer.

Close Thunderbird.

In Windows Explorer, look for a file cert8.db. Delete that file. It will be re-create when Thunderbird starts the next time.

Start Thunderbird. Do you still see the exception prompt?

Paul-H
Paul-H Question owner
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That fixed it

Many thanks for the help