Suddenly cant't send messages, SMTP server settings are correct, firewall is deactivated (using Thunderbird 60.8.0 on MacOS 10.14.5). What could be the problem?
Thunderbird keeps telling me that the SMTP server settings are wrong (see screenshot of error message), but they are correct and actually work just fine on my cell phone. Sending emails hasn't been working for about 3 months and came suddenly, I'm not sure whether it was after an update or not (might have been after an automatic update).
Chosen solution
Can you provide a link to the site with the netcup settings you're using? An old page here suggests mxf912.netcup.net on port 587, STARTTLS security, authentication = normal password, User name = part of address before @.
mxtoolbox.com indicates the server for netcup.net is smtp.netcup.net, supports STARTTLS.
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Chosen Solution
Can you provide a link to the site with the netcup settings you're using? An old page here suggests mxf912.netcup.net on port 587, STARTTLS security, authentication = normal password, User name = part of address before @.
mxtoolbox.com indicates the server for netcup.net is smtp.netcup.net, supports STARTTLS.
Hi, thanks for your time and help! The settings are shown inside the account – the up-to-date-server is mxf9a9.netcup.net.
Actually, the problem solved itself in the meanwhile – I made a Thunderbird update to the very latest version, and that was it. The problem was very erratic, Tunderbird kept telling me (among other things) the user name was incorrect (but it wasn't). I also received the attached error message a few times.
But all the settings were correct and after the update it's all just working fine again.
