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Pop certificate

Thunderbird Performance and connectivity
Balázs Meskó replied
Grzegorz Żukowski
Grzegorz Żukowski

Good day, I've had a problem for some time now and I can't figure it out. I get messages that the POP certificate is invalid. I use Cyber-Folks hosting and everything worked until now. I have a pop.etertech.pl domain and it works on that. But Kaspersky antivirus sends messages that the certificate is invalid. What should I do? Where should I look?

Good day, I've had a problem for some time now and I can't figure it out. I get messages that the POP certificate is invalid. I use Cyber-Folks hosting and everything worked until now. I have a pop.etertech.pl domain and it works on that. But Kaspersky antivirus sends messages that the certificate is invalid. What should I do? Where should I look?
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All Replies (1)

Balázs Meskó
Balázs Meskó
  • Moderator

Hi Grzegorz,

This usually happens because Thunderbird (and Firefox for that matter) does not use the system trust store, and Kaspersky is resigning every request with its own certificate while putting its root certificate into the system trust store. You can either disable the email protection component of Kaspersky, or import its root certificate into Thunderbird. They have a support article for this: https://support.kaspersky.com/common/compatibility/14620#block2

Regards, Balázs