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Can not send emails from Thunderbird

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  • 0 have this problem
  • Last reply by sfhowes

reiring
reiring
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Using Thunderbird 140.5.0esr (64-bit) email program, can not send emails. Get message: Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: Connection from 69.119.30.125 refused. Have multiple email accounts - all get same response. Have tried several computers -all get same response. Can receive emails with no problem. I have spent several hours with my service provider [Optimum] checking/changing Server settings to no avail. They claim all my settings are correct and say the problem is not on their end. On the Optimum website email – I can send emails with no problem. I installed Outlook and set it up to the same servers and can send emails from there so it would seem Thunderbird is the problem.

Running WIN10 on 1 machine, WIN11 on another. Both same issue

Using Thunderbird 140.5.0esr (64-bit) email program, can not send emails. Get message: Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: Connection from 69.119.30.125 refused. Have multiple email accounts - all get same response. Have tried several computers -all get same response. Can receive emails with no problem. I have spent several hours with my service provider [Optimum] checking/changing Server settings to no avail. They claim all my settings are correct and say the problem is not on their end. On the Optimum website email – I can send emails with no problem. I installed Outlook and set it up to the same servers and can send emails from there so it would seem Thunderbird is the problem. Running WIN10 on 1 machine, WIN11 on another. Both same issue
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sfhowes
sfhowes
  • Top 10 Contributor
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Two issues: first, you might want to try mail.optimum.net, 465, SSL/TLS, for the outgoing server.

https://www.optimum.net/FAQ/#/answers/a_id/216

Second, make sure each account is sending on its separate smtp server with the User Name matching the email address of the sending account:

https://support.mozilla.org/en-US/questions/1350593

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