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Unable to send messages using Thunderbird

adrian.lestrange
adrian.lestrange
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I am using Thunderbird v.115.5.2 and ever since the latest upgrade I cannot send messages. I get the message "sending messages failed ........ the connection to smtp.office365.com timed out". On my other computer the same message appears "sending the message failed ........ the connection to Outgoing server (SMTP) smtp-mail.outlook.com timed out". Sometimes, if I continue to try and send, the message will be sent after many, many attempts. Is there a solution?

I am using Thunderbird v.115.5.2 and ever since the latest upgrade I cannot send messages. I get the message "sending messages failed ........ the connection to smtp.office365.com timed out". On my other computer the same message appears "sending the message failed ........ the connection to Outgoing server (SMTP) smtp-mail.outlook.com timed out". Sometimes, if I continue to try and send, the message will be sent after many, many attempts. Is there a solution?

All Replies (3)

Matt
Matt
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  • Top 10 Contributor
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Personally I would start with disabling any antivirus software. That can have very detrimental effects on sending mail.

If you have a VPN, disable that and see if that improves mail sending. Some VPN's do not sopport email at all. Others require special settings from the company and in other instances the email provider refuses connections because the connection is coming from the wrong part of the world.

Wayne Mery
Wayne Mery
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  • Top 10 Contributor
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See also https://support.mozilla.org/en-US/kb/cannot-send-messages

Have you resolved your issue?

Agent virtuel
Agent virtuel
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Hello

Take a look ? https://connect.mozilla.org/t5/discussions/outlook-and-thunderbird/m-p/47664/highlight/true#M17031