I had funny experience today configuring notifications in Microsoft Data Protection Manager 2010. We have Postfix mail server instead of Exchange. Also we use SMTP authentication for outgoing mail from our users. DPM notifications configuration page has Username and Password fields for this. But simply using username and password of account registered in Postfix doesn’t work. It just says:
ID 2013
Details: Logon failure: unknown username or password
DPM needs this user to be registered in Active Directory. I have no idea why. So the simple solution to this was adding this account to AD with same password as in Postfix users database.
One more thing I’ve discovered is that for some reason Windows Server 2008 sends computer name without domain part in HELO command. Even though domain part is configured at System Properties. It wasn’t allowed in our mail server configuration. Solution to this was shifting of reject_non_fqdn_hostname option to the end of smtpd_recipient_restrictions (but before permit option) rule and addition of permit_mynetworks before it.
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