On the other hand, I don't know anyone with an @some-microsoft-property email address, so I don't know whether I'll be having trouble sending things there. I can reach Gmail and Yahoo (and after getting my own /64, Comcast) without trouble, though.
EDIT: Hmmm, mail-test.com seems to be a parked domain.
Apparently eShares is having the same problem. Shareholders with Microsoft-affiliated email addresses couldn't accept certificates.
Client host blocked using FBLW15; To request removal from this list please forward this message to [email protected] (in reply to RCPT TO command)
I did as it said and forwarded the message to that address, and got an automated reply and my IP removed a few days later.
Maybe your situation is different since you're not getting a bounce message, but try emailing that address if you haven't already.