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Sending of message failed

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  • 1 has this problem
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  • Last reply by pmcabinet

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Thunderbird is installed on my main PC and also my laptop. Both machines have the same account (albeit not synchronised of course). When I try to send any message from the laptop I get the error message "Sending of message failed. An error occurred while sending mail. The mail server responded: No SMTP service for unauthorized users. Please check the message recipient...xxx".

Messages are sent no problem from the PC. Outgoing server settings are identical for both laptop and PC.

I'm wondering how I have become an 'unauthorized user' on the laptop?

Maybe an update has caused a problem? - but both machines are on the same, latest update 91.3.0!

My wife and I share the laptop, and messages addressed to her are run through a filter into her folder; unorthodox, but there has never been a problem until recently. Presumably Thunderbird is causing this issue otherwise my ISP would reject messages from the PC as well?

Any ideas?

Thunderbird is installed on my main PC and also my laptop. Both machines have the same account (albeit not synchronised of course). When I try to send any message from the laptop I get the error message "Sending of message failed. An error occurred while sending mail. The mail server responded: No SMTP service for unauthorized users. Please check the message recipient...xxx". Messages are sent no problem from the PC. Outgoing server settings are identical for both laptop and PC. I'm wondering how I have become an 'unauthorized user' on the laptop? Maybe an update has caused a problem? - but both machines are on the same, latest update 91.3.0! My wife and I share the laptop, and messages addressed to her are run through a filter into her folder; unorthodox, but there has never been a problem until recently. Presumably Thunderbird is causing this issue otherwise my ISP would reject messages from the PC as well? Any ideas?

All Replies (2)

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Sounds to me like the outgoing server SMTP is configured not to use a password (authentication method) If you do not authenticate you are automatically unauthorized.

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Thanks for your comment Matt - but I can send messages quite happily from my PC even though T'bird Outgoing Server SMTP settings have 'No authentication' (see screenshot). My laptop has identical settings but will not send; at least it did not until this morning when my wife logged on to it and a Windows update was installed. Thereafter she could send emails. Could the update have affected it or was it a coincidence?

One other point: I run a Windows local account on my PC with automatic login, whereas my wife has to log in each time she uses the laptop. Maybe that is a factor where authentication is required? (Except she has never had to do that before.)

Should I nonetheless use authentication? I use automatic login because no-one else has access to my PC.