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Thunderbird says my email servers are not trusted

  • 4 replies
  • 1 has this problem
  • 715 views
  • Last reply by coffent

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Thunderbird has suddenly started claiming that certificates for three servers that I use are not trusted:

pop.googlemail.com:995 pop.gmail.com:995 pop.zoho.com:995

saying that they are attempting to identify themselves with invalid information and the certificates haven't been verified as issued by a trusted authority using a secure signature. I've been using all three for many years.

Why is it doing this? What should I do?

Thunderbird has suddenly started claiming that certificates for three servers that I use are not trusted: pop.googlemail.com:995 pop.gmail.com:995 pop.zoho.com:995 saying that they are attempting to identify themselves with invalid information and the certificates haven't been verified as issued by a trusted authority using a secure signature. I've been using all three for many years. Why is it doing this? What should I do?

All Replies (4)

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Who is the issuer of the certs Thunderbird is complaining about? Inspect the certs and check the 'Issued by' field.

What is your anti-virus software?

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For pop.googlemail.com (and I expect the others) it's Avast Web/Mail Shield (my anti-virus software), with a period of validity from Nov. 8 '17 to Jan 31 '18. The certificate viewer says "Could not verify this certificate because the issuer is unknown."

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Chosen Solution

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Thanks - that was the problem!