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Thunderbird 115.10.1 (64-bit) fails to send SMTP messages

  • 5 replies
  • 1 has this problem
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  • Last reply by Matt

mozilla414
mozilla414
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Since Thunderbird was upgraded to 115.10.1 (64-bit), it now fails to send SMTP messages with the following error.

Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) ***.mail.pairserver.com was lost in the middle of the transaction. Try again.

This affects all six(6) accounts in Thunderbird, all of them can receive and edit e-mail messages; however, all of them fail to send e-mail messages.

Prior versions of Thunderbird have worked with this configuration for many years.

Other e-mail clients such as Evolution do not have this issue and I have confirmed with my provider that Thunderbird is no longer sending e-mails.

Any thoughts on how to roll back Thunderbird until this issue is resolved?

Since Thunderbird was upgraded to 115.10.1 (64-bit), it now fails to send SMTP messages with the following error. Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) ***.mail.pairserver.com was lost in the middle of the transaction. Try again. This affects all six(6) accounts in Thunderbird, all of them can receive and edit e-mail messages; however, all of them fail to send e-mail messages. Prior versions of Thunderbird have worked with this configuration for many years. Other e-mail clients such as Evolution do not have this issue and I have confirmed with my provider that Thunderbird is no longer sending e-mails. Any thoughts on how to roll back Thunderbird until this issue is resolved?

All Replies (5)

david
david
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Changing releases doesn't usually fix things -- but sometimes they do. The prior version is at https://ftp.mozilla.org/pub/thunderbird/releases/115.10.0/ or you could upgrade to 115.11.

mozilla414
mozilla414 Question owner
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Thanks; however, sudo apt install thunderbird indicates: thunderbird is already the newest version (1:115.10.1+build1-0ubuntu0.23.10.1).

david
david
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Well, 115.11 was released on May 14th. 

 https://www.thunderbird.net/en-US/thunderbird/115.11.0/releasenotes/
mozilla414
mozilla414 Question owner
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115.11.0 seems to resolve the SMTP issue.

Well, maybe not so much. I added back the additional accounts and it does not work again... Only supports a single account at the moment.

Modified by mozilla414

Matt
Matt
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This forum is full of folk using ubuntu that are not aware their new version 24 of the product is using sandboxed snap installs of applications which are causing all sorts of issue with remote anything really. See https://ubuntu.com/core/docs/security-and-sandboxing