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I followed Flurdy's how-to for setting up a mail server on ubuntu. I can receive mails and use squirrelmail to read and send emails. However, I can't send emails through my server using my email client (thunderbird).

The mail.log shows: "SASL authentication failure: incorrect digest response"

Can somebody explain what that should tell me? What can I do to get further information (log files or increased verbosity)?


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Non-verbose logs from your mail.* log concerning one attempt to send mail would tell us what postfix thinks of it.

It is quite likely you did not set up TB to use STARTTLS with secure authentication; another possibility is an incorrect auth mechanism configuration.

Consult the official documentation, not some unknown tutorial, for assistance.

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I was about to give up after SASL authentication failure: incorrect digest response and SASL CRAM-MD5 authentication failed: authentication failure, etc. Trying to send from Thunderbird for a full day to only see the failures. What worked for me just now was to change a smpt server setting Edit > Account Settings... and then ... Outgoing Server(SMTP). Edit the servers in the list on the right and change Authentication method from Encrypted password to Normal password.

Good luck :)

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This makes it work yes, but it doesn't solve the problem of not being able to use encrypted passwords. – Chris May 22 at 10:30
Yes, I see what you mean. I confess I was not after encryption; I just wanted to get the damned thing to work! It was such a arduous task to install and configure this mail system. I won't do it again. Thank you for your comment - I agree with you. – Randy Skretka May 24 at 19:11
It worked for me too, disabling encrypted passwords. I also make sure that it will only allow a connection with tls so the password isnt transmitted insecurely, I would still like it encrypted but il get there some day, for now im just happy that i can connect from my client. – Chris yesterday

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