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Non-overridable TLS error occurred.

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I have been using three email accounts on Thunderbird, all for a long period of time, and all without any issue. Recently the one listed below has not been backing up, and I receive this message. I am not techie at all, so any response needs to be dummy down to a 5th grader level. Thanks!

"Non-overridable TLS error occurred. Handshake error probably the TLS version or certificate used by server mail.q.com is incompatible."

I have been using three email accounts on Thunderbird, all for a long period of time, and all without any issue. Recently the one listed below has not been backing up, and I receive this message. I am not techie at all, so any response needs to be dummy down to a 5th grader level. Thanks! "Non-overridable TLS error occurred. Handshake error probably the TLS version or certificate used by server mail.q.com is incompatible."

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Essentially, the error means that Thunderbird cannot communicate securely to the server. It's best to wait a few hours and try again later.