When I want to synchronize Allocatus with Project, I get the following error:
Mailbox unavailable.
The server response was: 5.7.1 Unable to relay
What can I do?
The configured SMTP Server has to allow relaying to the Project Server IP-address. Ask your Exchange Administrator to allow relaying.
You can find a description here:
Exchange 2007: http://technet.microsoft.com/en-us/library/bb232021(v=exchg.80).aspx
Exchange 2010: http://technet.microsoft.com/en-us/library/bb232021(v=exchg.141).aspx