Thank you, finally solved. The problem was that I had SMTPTLS configured and while the installer.pl script did not find anything wrong, something WAS wrong.
After changing to SMTP without authentication, all works :-)
The error message was misleading….
Regards
JZ
From: otrs-bounces@otrs.org [mailto:otrs-bounces@otrs.org]
On Behalf Of David Boyes
Sent: Friday, February 22, 2013 4:57 PM
To: User questions and discussions about OTRS.
Subject: Re: [otrs] Couldn't send mail: 550 5.7.1 Client does not have permissions to send as this sender
unfortunatelly, there is no error. The the last entry in SMTP log (of Exchange server) is successfull authentication and that´s all.
Besides, the install script http://localhost/otrs/installer.pl found IMAPS and SMTPS is working fine….
Then the problem is in the list of hosts that that SMTP server(s) are allowed to relay. You may be allowed to authenticate, but that doesn’t mean that the SMTP server will relay your mail.