Microsoft Cloudmail-server being blacklisted MY problem???

One of our users got a notification today after sending an email. Said a server with a certain IP-address is listen on a blacklist with Trend Micro RBL+.

So I thought to do the right thing (besides requesting to be put off the blacklist) and contact Microsoft Technical Support about it, since this has potential to affect their other customers as well.

Basically, I was told I should request for the IP-address to be removed from the blacklist, even though it’s their server….. Weird…..