This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Rohkem teavet

Getting error message as seen in screen capture.

  • 5 vastust
  • 2 on selline probleem
  • 13 views
  • Viimati vastas christ1

more options

This has just shown up...not sure why. This is what I am seeing. Annoying since it takes multiple clicks on "cancel" to get rid of it. What has changed? Recently updated Kaspersky Total security, but this seems to be related to Thunderbird?

This has just shown up...not sure why. This is what I am seeing. Annoying since it takes multiple clicks on "cancel" to get rid of it. What has changed? Recently updated Kaspersky Total security, but this seems to be related to Thunderbird?
Attached screenshots

All Replies (5)

more options

Press the 'View' button and inspect the certificate - see attached screenshot for instructions. Who is the issuer of the cert? Please post another screenshot of the certificate viewer window with the issuer information visible.

more options

Thank you for your response. I am not sure why I could net get this to come up earlier. Below is what I see. It is apparently a Kaspersky issue. Grrr. If you can help I would be grateful. If not, no biggy, will contact Kaspersky in the AM.

more options

Shouldn't POP be using 995?

more options

Well, I changed the port to the suggested 995....no joy. Not sure what the port has to do with kaspersky. As previously stated, I will be contacting Kaspersky in the AM. Thanks for the help.

more options

Kaspersky is issuing a cert for a Google server, and thus basically performing a man-in-the middle attack on your secure connection. Thunderbird doesn't know about Kaspersky as a Root CA, and gives you the exception prompt.

See https://support.mozilla.org/en-US/kb/connection-untrusted-error-message#w_the-certificate-is-not-trusted-because-the-issuer-certificate-is-unknown