I have been through this before but wanted to check if there is now an easier way....
Just set up a new SM server. Initial tests to an @outlook.com address results in an immediate bounceback:
Reason: Remote host said: 550 OU-002 (SNT004-MC4F26) Unfortunately, messages from 220.127.116.11 weren't sent. Please contact your Internet service provider since part of their network is on our block list. You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors
Looks like the IP block we have received has a bad rep with the Outlook.com servers.
So, apart from going through their SNDS request is there anything else that can be done?
Just to note, the IP address is not on any public block/abuse lists and the sending server is doing all it can!