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Uknown error is not a good error message. There is particular reason to stop sendind mail. How to know this reason?

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  • 1 has this problem
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  • Last reply by christ1

sm1th
sm1th
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Sending of the message failed. The message could not be sent using Outgoing server (SMTP) mx.uis.kiev.ua for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again.

This message apears after thunderbird update. Nothing wrong with server. Old version work perfectly. WHAT particular reason not to send message?

Sending of the message failed. The message could not be sent using Outgoing server (SMTP) mx.uis.kiev.ua for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again. This message apears after thunderbird update. Nothing wrong with server. Old version work perfectly. WHAT particular reason not to send message?

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christ1
christ1
  • Top 25 Contributor
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https://support.mozilla.org/en-US/kb/cannot-send-messages