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Sending of the message failed.

  • 6 replies
  • 2 have this problem
  • 44 views
  • Last reply by Sillycat41

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In the past week I have received this error message several times when trying to send an email with T-bird 91.7.0. Most emails are sent but every once in a while they won't go. I can't figure why. Any ideas? Something to do with the content?

Sending of the message failed. The message could not be sent using Outgoing server (SMTP) mail.tds.net for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again.

In the past week I have received this error message several times when trying to send an email with T-bird 91.7.0. Most emails are sent but every once in a while they won't go. I can't figure why. Any ideas? Something to do with the content? '''Sending of the message failed. The message could not be sent using Outgoing server (SMTP) mail.tds.net for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again.'''

All Replies (6)

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Hello there sillycat. We have read your message. We try to help you.

Oké your message could not be send for going out to the outgoing server with reasons.

Do you have a error number?


https://support.mozilla.org/en-US/kb/cannot-send-messages


Greetings Firefox volunteer.

Modified by Display name. день сумо

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There was no error number, just this message:

Sending of the message failed.

The message could not be sent using Outgoing server (SMTP) mail.tds.net for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again.

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Hello there again silly cat.

Can you send me your Smtp configuration?


It could be that it is your Smtp settings. A picture is oke.


Greetings Firefox volunteer.

Modified by Display name. день сумо

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Sorry... I should have given more details. My ISP's SMTP settings are correct. I can send several emails with no problem and then this message pops up on the next email. Then I can send several email again with no problem. It's very erratic. I'm wondering if it has something to do with the content of the email... for example when I'm forwarding a certain web site.

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I suggest you log your sending of mails so there is something to go on when it fails.

See https://thunderbirdtweaks.blogspot.com/2021/10/logging-mail-sending-in-thunderbird.html

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Thanks Matt... I'll give this a try.