So the other day I tried to send an email to a friend (who uses Hotmail). The email bounced with:

"SMTP error from remote mail server after MAIL FROM:<(myemail)> SIZE=1941:

    host mx2.hotmail.com [65.54.188.72]: 550 SC-001 (BAY0-MC1-F14) Unfortunately, messages from 144.76.45.203 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."

Which seemed odd. I checked my server's mail logs and the amount of emails it has sent to Hotmail over the last 2 months could be counted on one hand. All of which I could personally identify. So I went to the listed site, filled out the (stupidly long) delisting form.

A few minutes later I received this:

"We have completed reviewing the IP(s) you submitted. The following table contains the results of our investigation.

Not qualified for mitigation

144.76.45.203

Our investigation has determined that the above IP(s) do not qualify for mitigation.

Please ensure your emails comply with the Outlook.com policies, practices and guidelines found here: http://mail.live.com/mail/policies.aspx.

To have Deliverability Support investigate further, please reply to this email with a detailed description of the problem you are having, including specific error messages, and an agent will contact you."

Seriously? They don't tell you why it was listed in the first place, don't tell you why you're still listed and then refuse to delist you. Has anyone else had to deal with this stupidity before and does anyone have any recommendations?

This needs to be resolved but I'm hitting an invisible wall here with no information what-so-ever to go on and I see no way of following this up with Microsoft.