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Norton blocks Thunderbird email due to "expired certificate"

Thunderbird Encryption
zizumara replied 2 päeva tagasi
zizumara
zizumara

I have Thunderbird installed on Windows 11 along with Norton 360. Today, my connection to the AT&T e-mail server suddenly disconnected and I immediately got a pop-up notification that Norton detected a problem with a security certificate. When I inspected the details, it indicated that the certificate for inbound.att.net had expired (the range of valid dates on the certificate actually listed the current date as the last valid date). After several infuriating calls with AT&T support and Norton support, I figured out that simply disabling Norton e-mail protection allowed me to access my e-mail account.

Multiple web searches on similar issues suggested that since Thunderbird has its own certificate storage, fixing the problem involves locating the Norton certificate file and importing it using Thunderbird's certificate manager. Unfortunately, that solution appears to be applicable for first-time Thunderbird installation, and I when I tried it I was informed that the certificate was already installed. Another web search suggested that I should go to the Authorities tab and remove the entry for "Norton Email Protection". Unfortunately, the entry that I found was for "Norton Web/Mail Shield", which according to at least one source is not the same thing, so I am afraid to remove it.

So my question is has anyone else encountered this same problem, and is the correct approach to remove the Norton Web/Mail Shield authority before importing Norton's certificate file?

I have Thunderbird installed on Windows 11 along with Norton 360. Today, my connection to the AT&T e-mail server suddenly disconnected and I immediately got a pop-up notification that Norton detected a problem with a security certificate. When I inspected the details, it indicated that the certificate for inbound.att.net had expired (the range of valid dates on the certificate actually listed the current date as the last valid date). After several infuriating calls with AT&T support and Norton support, I figured out that simply disabling Norton e-mail protection allowed me to access my e-mail account. Multiple web searches on similar issues suggested that since Thunderbird has its own certificate storage, fixing the problem involves locating the Norton certificate file and importing it using Thunderbird's certificate manager. Unfortunately, that solution appears to be applicable for first-time Thunderbird installation, and I when I tried it I was informed that the certificate was already installed. Another web search suggested that I should go to the Authorities tab and remove the entry for "Norton Email Protection". Unfortunately, the entry that I found was for "Norton Web/Mail Shield", which according to at least one source is not the same thing, so I am afraid to remove it. So my question is has anyone else encountered this same problem, and is the correct approach to remove the Norton Web/Mail Shield authority before importing Norton's certificate file?

All Replies (2)

Wayne Mery
Wayne Mery
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ATT has had problems. They should have fixed it by now.

zizumara
zizumara Küsimuse esitaja

Yes, I re-enabled Norton protection and the problem is gone now. AT&T support was clueless. I gave up trying to explain the problem to them. Their support staff only seems to be able to follow a script that had nothing to do with the problem. Telling them "the security certificate to your server has expired" is gibberish to them.

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