Microsoft 365 Mailserver Blacklisted by Spam Cop

Question

Customers are reporting issues with email delivery because the IP address of the Microsoft 365 mail server is listed on Spamcop.

IP's:

40.107.22.51

https://www.spamcop.net/bl.shtml?40.107.22.51

40.107.21.76

https://www.spamcop.net/bl.shtml?40.107.21.76

Thank you for your attention!

Answer 1

Spamcop isn't responsible for Microsoft allowing SPAM and phishing through their servers. Not blocking them just because they're a big email provider would be irresponsible. The recipients or the folks being blocked should be yelling at someone, Microsoft, not Spamcop.

I don't disagree with you, but blocking whole IP ranges from a known vendor that hosts much of the email on the internet is shortsighted and lazy. They could be using better filtering techniques instead of blocking the O365 ranges. That's like them blocking Gmail.com addresses because they had some reported spam, of course they are going to get spam from the ranges.

Answer 2

What a garbage response...

O365 sends out emails for multiple tenants from any number of IPs which we have no control over.

Of course spam is going to come from O365, so you just block everyone???

They don't care about us senders, do the recipients have to yell at them?

Edit:
Looks like Microsoft is "Working on it" https://admin.microsoft.com/Adminportal/Home#/servicehealth/:/alerts/EX703958

Spamcop isn't responsible for Microsoft allowing SPAM and phishing through their servers. Not blocking them just because they're a big email provider would be irresponsible. The recipients or the folks being blocked should be yelling at someone, Microsoft, not Spamcop.

Answer 3

I have customers reporting the same issue. I've had multiple cases open with Microsoft on this and another similar issue.

Most recent IP that was rejected 40.107.236.100 at the time of writing this.

Hopefully there is a fix to this soon.

Answer 4

It's not perfect, but it works. Given each attempt to send mail can routed differently, we advised our personnel to try again and had success sending the same message back through Microsofts servers. It's not ideal, but can work until Microsoft can get a grip on their servers.

Answer 5

Having the same issue. Given the number of folks using Microsoft's mail servers, I would hope it's a priority to get this cleaned up.

IP: 40.107.236.100