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.

Or you can add an exception…

plus, now, i cannot seem to add my gmail account. my current account with issues is a msn.com ccount

That error message is common where folk use an anti virus that thinks it is above the SSL system and asks to be incorporated into the certifying authorities database. Avast is one such product.

Another cause is the Microsoft family protection stuff they bundle with windows. It really only works with Microsoft products like Edge.

Basically I think you have anti virus/ Security suite problems, but to confirm.

Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, OSX

If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.

I dont use security or av of anykind. This didnt happen until thunderbird updated itself

josbourn1 said

I dont use security or av of anykind. This didnt happen until thunderbird updated itself

Then as a windows user you probably have a virus. Seriously. Nothing?

What do you meen "nothing". Im not a newb. I control my security. I just do not have a constant running av. Causes too many problems. Microsoft stuff is a joke at best. I have scanned tbe system. Besides its a very recent build. And again, why immediately after the mozilla update did it happen? I meen immediately! Perfect an hour before and all i did was restart thunderbird. Why is it that its immediately another program or a virus? Is it truly impossible that your update caused problem?

josbourn1 said

Is it truly impossible that your update caused problem?

Not impossible, but very unusual.

It is also a common issue when servers do not have recent or currently acceptable cyphers for TLS.

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