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Thunderbird fails to send mail using any of my mailboxes

  • 3 uphendule
  • 1 inale nkinga
  • 10 views
  • Igcine ukuphendulwa ngu AgnesRM

Andrew
Andrew
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TB drops sending mail with the following error: "Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) smtp.gmail.com failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again."

My SMTP settings are all set as in the screenshot (I've painted over my email address). I get the same error for any other email I have (outlook etc). Receiving mail works as usual, the problem persists only with sending mail.

Thunderbird version 91.5.0 (64-bit), platform Win7 64-bit.

What I've tried so far: 1. Rebooting TB into troubleshooting mode, disabling any extensions 2. Clearing passwords from Thunderbird and revoking OAuth2 tokens (or, in case of outlook, only clearing passwords) 3. Accessing from under Ubuntu 20.04 LTS, also Thunderbird (no luck).

I used the same Internet connection for all my tests, and it recently changed (prior to that I didn't seem to have any problems). It wasn't a change of the provider, more of a change of location (I moved a few blocks to the side). Obviously, Gmail's web interface works just fine.

Any suggestions?

TB drops sending mail with the following error: "Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) smtp.gmail.com failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again." My SMTP settings are all set as in the screenshot (I've painted over my email address). I get the same error for any other email I have (outlook etc). Receiving mail works as usual, the problem persists only with sending mail. Thunderbird version 91.5.0 (64-bit), platform Win7 64-bit. What I've tried so far: 1. Rebooting TB into troubleshooting mode, disabling any extensions 2. Clearing passwords from Thunderbird and revoking OAuth2 tokens (or, in case of outlook, only clearing passwords) 3. Accessing from under Ubuntu 20.04 LTS, also Thunderbird (no luck). I used the same Internet connection for all my tests, and it recently changed (prior to that I didn't seem to have any problems). It wasn't a change of the provider, more of a change of location (I moved a few blocks to the side). Obviously, Gmail's web interface works just fine. Any suggestions?
Ama-screenshot ananyekiwe

All Replies (3)

AgnesRM
AgnesRM
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You seem to have covered a lot on the Thunderbird side. Perhaps something in Gmail is causing the problem? Just in case, make sure Gmail has IMAP "on" - log in with webmail to the Gmail account, then Settings - Forwarding and POP/IMAP - check that Enable IMAP is on. There are some other tips in Gmail help "Check Gmail through other email platforms"

Andrew
Andrew Umnikazi wombuzo
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Thanks for replying. Unfortunately, I checked it and the problem still persists. One of my current assumptions is that my router and/or access point somehow blocks any SMTP access. Sadly I have no idea how to verify that.

AgnesRM
AgnesRM
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Your virus scanning software or firewall software may do that too. Ensure that Thunderbird has permission, or make an exclusion to prevent scanning/blocking of TB. How to do that depends on the virus and firewall software you use. I am not sure whether your test with Ubuntu would have eliminated that possibility.