In the last image - SMTP Server Try: server name: smtp.mediacombb.net SMTP Port :587 Connection Security: STARTTLS Authentication method: Normal Password Usually Username is the full email address for most servers, but I do note on the website info page it does say use the part of email address that is before the @ symbol, so for now keep username the same, change the bits I've highlighted. Click on all the OKs and restart Thunderbird.

Test sending.

I had already tried changing the port. I did as you ask and changed the security plus the port. Closed and restarted and made sure the changes were there.

I got the same failure when trying to send.

How many mail accounts do you have in thunderbird?

Please note: each mail account - email address - will require it's own smtp server. In Account Settings In the last image - SMTP Server There is a 'Description' field - type in the email address of the mail account. click on OK

Then check the correct mail account is using the correct smtp server.

Select the email address/mail account name in left pane on the right it will say 'Outgoing server (SMTP)' Does it say the same email address as the actual mail account email address ? If no then click on the drop down and select the one that says same email address. click on OK

restart Thunderbird.

If that still fails: Suggest you try changing the username to full email address.

If you are using a version 68 or earlier:

Menu app icon > options > Options > Advanced > Network & Disk Space click on 'Settings' What is selected ? Suggest : 'Use system proxy settings'

If this is already selected:

Restart Computer in 'Safe Mode with Networking' Test sending.

Thanks Toad-Hall,

The next to the last message last sentence solved the problem; changed username to full email address.

Not sure if I would have ever come up with that, since Thunderbird filled in all of that information.

Good to hear all is ok again and many thanks for feedback.

Sadly, the webpage for mediacombb.net that offers info is not fully correct. They state very clearly the username is only the part before the @ symbol. This is incorrect for accessing server. But, because I've helped people access alot of various servers, I knew this was not the standard practise and hence guessed it could be the problem.

Thunderbird can only access their servers using specific settings that the email provider (mediacombb.net) has chosen to use. As you have found, they are very specific in order to gain access to server. So, it would be reasonable to assume that the email provider would know what the server settings should be for their own pop, imap and smtp servers. Sadly, they did not, so just said it was Thunderbirds problem.

Thunderbird does have a database that it uses to try to set up configuration settings based on information reported or offered, but it does not have all of them.