I have recently bought VPS with a new IP address (146.59.239.142) which is by default blacklisted at Microsoft and I need to register it with Microsoft Smart Network Data Service to whitelist it, otherwise I cannot and will never be able to send emails to Microsoft (Hotmail, Outlook and Live.com).
This usually isn’t something you can fix on your own. Since the IP belongs to OVH, only they can confirm ownership through those abuse/postmaster addresses. Your best options are:
Keep pushing OVH support and clearly ask them to confirm the IP in SNDS on your behalf.
In the meantime, use an external SMTP service (like a transactional email provider) so you’re not blocked by Microsoft.
Avoid sending directly from that IP until OVH resolves it, or Microsoft may keep rejecting it.
Unfortunately, without OVH’s involvement, SNDS registration won’t go through.
Because MS JMRP form is broken (and I have contacted MS for that). I have sent a support request for MS (for the 9th time) but this time I replied to their automated message (this is the trick) with details about the issue and then an MS support technician helped delist my IP manually which solved my problem.