Recent answers to Cannot send or receive from gmail account in Thunderbirdhttps://support.mozilla.org/si/questions/13049692020-09-21T01:51:05-07:00Thanks for reply...I tried your recommendations but had the same results. When I tested gmail throug2020-09-21T01:51:05-07:00zpagosahttps://support.mozilla.org/si/questions/1304969#answer-1351794<p>Thanks for reply...I tried your recommendations but had the same results. When I tested gmail through the web based interface I was foreced to use two step verification through the gmail app on my phone. Based on what you said about OAuth2 and 2-step verification it looks like I might have to switch over to IMAP from POP....
</p>You might want to double-check the settings that you have (incoming and outgoing) to be the same as 2020-09-18T16:50:21-07:00firefox200915https://support.mozilla.org/si/questions/1304969#answer-1351118<p>You might want to double-check the settings that you have (incoming and outgoing) to be the same as mentioned on google page (server, port, ssl/tsl).
If all are fine, test by changing one (1) of the options and after that restart Thunderbird. When it start see if the changes made by you previous are still as were last saved by you (or if it have returned to the value which was before your change - suspecting some corruption files)
</p><p>Later Edit: If you're using port 587, the security should be STARTTLS. SSL/TLS works on port 465. The recommended authentication is OAuth2, together with allowing 'less-secure apps'. If you applied 2-step verification, the authentication has to be either OAuth2 or with an app password.
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