SOLVED Cpanel Server email is rejecting Office 365 email for bad PTR record.


Nov 26, 2019
Mesa, AZ
cPanel Access Level
Root Administrator
UPDATE: ADDED A DMARC Record based on microsofts doc here:Use DMARC to validate email - Office 365

Now the emails are getting thru and not being rejected.

Here's the symptom. I wanted to post the fix in case someone else searches for the same issue:

My GoDaddy O365 email gets delivered everywhere but my Cpanel Server. All the sudden today, it has started rejecting my emails which will impact my business. I have spent the last 5 hours searching MS docs, Cpanel docs and everything else in the world. What I gather is Microsoft has many IP addresses that are used to send email and thats where the issue is because you can't make a ptr record for all of them.
Does anyone have a solution to this issue? PLEASE? I have included the complete reject email below. I don't care that my email addresses and domain names are visible because they're all over the place anyway.

I sincerely appreciate your time and assistance with this issue!
matt caswell

A security check at failed due to misconfigured settings at . .Office
Action RequiredRecipient
Misconfigured PTR record
How to Fix It
The recipient's email server at performed a security check against your message and the check failed. To fix this, forward this non-delivery report (NDR) to your email admin.
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More Info for Email Admins
Status code: 550 5.7.363

It appears that the recipient's email server at performed a reverse DNS (rDNS) lookup security check to verify that the IP address the message is coming from is associated with the sending domain, and the lookup failed. It appears that the pointer (PTR) record for isn't set up correctly.

Set up or fix your domain's PTR record - If you're the admin for, work with your DNS hosting provider (your domain registrar, Web hosting provider, or ISP) to correctly set up a PTR record for your domain. If you're using Office 365 to manage your DNS records note that PTR record creation and management isn't supported in Office 365, so you'll have to change your DNS management to a DNS host outside Office 365. Refer to this article for more information and instructions: Change how DNS records are managed with Office 365.

Unfortunately, Office 365 Support can't help you fix these kinds of externally reported errors because Office 365 doesn't support PTR record management.
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