Unable to send emails to outlook

The problem still exists.  I got an S3150 today, attempting to send email to mailto:email address removed for privacy reasons (how apropos).  It looks like Microsoft has decided I am on a block list.  SpamHaus says otherwise, both IP and domain.  And since I am the C-suite, admin, postmaster, and everything for the IP/domain, I also beg to differ.  Based on the error message, I think that MS believes that nothing smaller than a class C exists in the world, and because of that my /29 is blamed for the actions of someone else in the /24.  So far, the only thing I have been able to accomplish trying to talk to someone at MS is to get my home phone number put on some sort of block list -- I am no longer able to do anything other complain about some outlook.com issue.  I had MUCH better luck getting this resolved when dealing with Comcast.  Faster and easier.  AND resolved.