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Thunderbirs SMTP error

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  • 2 have this problem
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  • Last reply by benheuser

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Since this morning I am unable to send Mail via Thunderbird. I am getting the error message:

'Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) securesmtp.t-online.de failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again'

I can still receive emails and I can send emails with the same outgoing server settings from a mobile device in the same WIFI. I tried re-adding one of the accounts. This problem occurs on all my email accounts.

I am working on Ubuntu 20.04 and have installed Thunderbird version 102.9.0.

Since this morning I am unable to send Mail via Thunderbird. I am getting the error message: 'Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) securesmtp.t-online.de failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again' I can still receive emails and I can send emails with the same outgoing server settings from a mobile device in the same WIFI. I tried re-adding one of the accounts. This problem occurs on all my email accounts. I am working on Ubuntu 20.04 and have installed Thunderbird version 102.9.0.

Chosen solution

The problem resolved itself after a few hours. I still don't know the reason.

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Chosen Solution

The problem resolved itself after a few hours. I still don't know the reason.