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Thunderbird stopped sending mail

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  • Last reply by Wayne Mery

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Using 115.5.2 and macos 13.6.3. Suddenly on or before 12/10/23 Thunderbird stopped sending email. Receiving continues to work. No changes to software recorded (either TB or OS. Have reset all parameters according to ISP (charter.net). Installed Mailspring and it send mail without issue using the same parameters. Have reinstalled TB. I have not discarded all TB files as I have huge archive of emails I cannot loose. Is/Are there specific setting files that I can reset without loosing data?

Using 115.5.2 and macos 13.6.3. Suddenly on or before 12/10/23 Thunderbird stopped sending email. Receiving continues to work. No changes to software recorded (either TB or OS. Have reset all parameters according to ISP (charter.net). Installed Mailspring and it send mail without issue using the same parameters. Have reinstalled TB. I have not discarded all TB files as I have huge archive of emails I cannot loose. Is/Are there specific setting files that I can reset without loosing data?
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Such issues tend to be caused by antivirus or the mail provider. Have you seen https://support.mozilla.org/en-US/kb/cannot-send-messages

And have you resolved your issue?