How to get an external Mail-Server whitelistet on OVH?

Hi OVH Community,
we've got a problem from outside:

It seems the the OVH-Mailserver put the IP of my customer (for whatever untold reason) on a blacklist. As a result he can't send any mails to customers of ovh.

Normally there are ways to go in such a case. Either a mail at postmaster or there's a form or similar to be found on the website.

I sent a mail at postmaster describing the problem but didn't get any reaction so far. (My guess would've been some automated reply at the least)

My question to the community is what you would propose in this case. Naturally, I checked the support material. And I also checked the mailserver/IP which is denied by the ovh mailservers. It appears on no public blacklists and DKIM/SPF/Reverse DNS Lookup is fine. Also other servers accept the mails just fine.

B.t.w.: Such errors are looking like this one (the server is disconnected without even a status code or message):
Jan 19 17:10:03 mx2 postfix/smtp[5356]: 27F1EA27C5: to=, relay=mx3.mail.ovh.net[91.121.53.175]:25, delay=34036, delays=34036/0.02/0.12/0, dsn=4.4.2, status=deferred (lo
st connection with mx3.mail.ovh.net[91.121.53.175] while receiving the initial server greeting)

Thanks for any answer. :slight_smile: