Been around since dos 1.x back in the Peter Norton and Bill Gates day.
Sad day when you open a ticket and get a Sbaitso reply!
https://www.youtube.com/watch?v=sV3pYZZ2jEw
Microsoft needs a better system ip bocking system that's for sure.
If your ip is not blacklisted in other RBL's , good sending reputation and high sending score at Return Path it should not be permanently blocked due to span at Microsoft. Their system is flawed badly!
Burning ips is not the answer. Finding good ip4's is becoming almost impossible.
Eventually the trashcan needs to be cleaned out.
Don't blame Microsoft for taking a stand. It's getting the issue resolved where they are wronging other provider.
Had to change outgoing mail server ip addresses and assign statics for larger companies.
Took weeks finding something that was not already back-listed at AT&T and Microsoft.
Still trying to get new ip addresses white-listed with other providers like Yahoo and AOL.
New or out of the sandbox used ip4's take time building a reputation.
Amazing how one infected client can destroy your ip sender reputation and get you blocked with no return at Microsoft. Must say the truth is "Mark as Answer" "Don't bother Microsoft will not unblock you"