Outlook 2013 perpetuates an issue with the Test email that is sent when creating a new email account or profile.
The issue has been there since much older versions of Outlook (like Office 97) but was always allowed to error gracefully, report, and be ignored.
The issue is that the Test Email does not have a date in the header. After all why would we want a date on a test email? (dripping with sarcasm!) other than to make it compliant with internet standards (which apparently in the RFC the date is optional, common sense says that adding todays date cannot be that hard, but I digress.
So, Outlook 2013 now has no option to accept the failure becuase ‘the server must be faulty’.
The error is 552 no date in header or similar depending on which flavour of server is reporting it.
For SME Server this could be remedied by allowing no header emails from within the local network, which should not present an issue for spam (which assumes that spammers do not worry about dates either) as it is on the local interface and not opening it up to the public.
This is documented in the SME Server Wiki but it is a simple snippet for a custom template created like this:
mkdir -p /etc/e-smith/templates-custom/var/service/qpsmtpd/config/peers/local
echo “# 17check_basicheaders disabled by custom template” > 17check_basicheaders
The last command resets the mail handling and you should be ok to run the test from the local network. Remote connections, unless on the VPN, will not work as the external interface will continue to reject the message without the date.