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Problem after upgrading - Communication participant's certificate has an invalid signature.

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  • Last reply by warroa59

warroa59
warroa59
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Hello, My Thunderbird has been recently upgraded to the newest version 78. Unfortunately there is a problem with sending, receiving or saving the messages. My email provider has checked everything on the server and assures me that everything is correct with protocols etc. He advised me to delete my account and create it again which I doubt may work. Can You help me somehow? Best Regards, Anna

Hello, My Thunderbird has been recently upgraded to the newest version 78. Unfortunately there is a problem with sending, receiving or saving the messages. My email provider has checked everything on the server and assures me that everything is correct with protocols etc. He advised me to delete my account and create it again which I doubt may work. Can You help me somehow? Best Regards, Anna

Modified by Wayne Mery

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Wayne Mery
Wayne Mery
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Does https://support.mozilla.org/en-US/kb/thunderbird-78-faq#w_after-upgrading-to-thunderbird-78-i-cannot-get-or-send-email-messages help?

warroa59
warroa59 Question owner
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Hello, Thank You for your answer. I have asked the provider about the protocols and they said that everything is correct so I didn’t do the config process You have suggested. I’m not so “fluent” with this stuff either:(

Wayne Mery
Wayne Mery
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In https://support.mozilla.org/en-US/questions/1312165 you posted "I can't still send, receive, save any messages. You have suggested to check the security protocols but my provider says that everything is correct. They work on TLSv1, TLS1.1 oraz TLSv1.2. Everything works fine when I log through the web page. But Thunderbird pops up with some issues: "sending the message has failed. Communication participant's certificate has an invalid signature. The configuration needs to be corrected" or something like this, when trying to save the message: "it's not possible to copy the the draft of the message o the sketch folder due to network or file access errors""

Wayne Mery
Wayne Mery
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What is the exact wording of the error message for "Communication participant's certificate has an invalid signature" ?

warroa59
warroa59 Question owner
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More or less like this: "Sending of the message failed. The communication participant certificate has an invalid signature. The configuration related to (here is the name of my server) must be corrected". As I have mentioned before, my provider has duble checked it and the server is fine.

warroa59
warroa59 Question owner
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I have also tried to to change the settings according to the link: https://support.mozilla.org/pl/kb/thunderbird-78-faq#w_how-to-enable-outdated-security-protocols-tls-1-0-and-1-1 But it didn't help at all. Could You please help me to solve it somehow?? Regards, Anna