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Thunderbird 102 will not send emails.

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  • 0 have this problem
  • 12 views
  • Last reply by Toad-Hall

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I installed the latest Thunderbird 102 version. I set up my email accounts as I did in Microsoft Mail that came with Windows 10 on my Dell PC. It receives emails perfectly, but will not send emails. Says it lost contact with the SMTP Server or the SMTP Server terminated the connection and I should check and verify my SMTP Service information. My MS Mail is working fine, sending and receiving emails just fine. Even though I setup my email accounts on Thunderbird with the same settings that worked on MS Mail, Thunderbird 102 will not send emails. The only difference I see is MS Mail supports SSL encryption, but I found no option for SSL in Thunderbird. Does Thunderbird not support SSL?

Thank you.

Randy [email removed from public]

I installed the latest Thunderbird 102 version. I set up my email accounts as I did in Microsoft Mail that came with Windows 10 on my Dell PC. It receives emails perfectly, but will not send emails. Says it lost contact with the SMTP Server or the SMTP Server terminated the connection and I should check and verify my SMTP Service information. My MS Mail is working fine, sending and receiving emails just fine. Even though I setup my email accounts on Thunderbird with the same settings that worked on MS Mail, Thunderbird 102 will not send emails. The only difference I see is MS Mail supports SSL encryption, but I found no option for SSL in Thunderbird. Does Thunderbird not support SSL? Thank you. Randy [email removed from public]

Modified by James

All Replies (1)

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Not sure what server settings you are using but I would try the following as it works for most SMTP connections.

  • Port: 587
  • Connection Security: STARTTLS
  • Authentication Method: Normal Password
  • User Name = full email address

Password = same password you use when you logon to see webmail account. Same as used for incoming.

It would help if you told us what server you use eg: gmail, comcast, BT, etc

  • Menu icon > More Troubleshooting Information
  • Under 'Mail and News Accounts' section
  • Copy all the info and post it into this forum question.

You should also make sure your Firewall has Thunderbird listed as an allowed program.