[Okta Webinar] Learn how to a build a cloud-first strategyRegister Now

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 2256
  • Last Modified:

Recipient email server rejects senders email (Office 365) due to incorrect PTR record

I have a customer on Office 365.  When they send an email to a particular recipient, they get an error:

A security check at "recipientdomain.com" failed due to misconfigured settings at "sendersdomain.com."

Status code: 550 5.7.363

It appears that the recipient's email server at recipientdomain.com 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 sendersdomain.com isn't set up correctly.

I know that if the sending email server is in-house, I would contact the ISP and have them create an rDNS entry but how do we fix this if the sending server is Office 365?
0
ptsolutionsinc
Asked:
ptsolutionsinc
  • 2
1 Solution
 
Vasil Michev (MVP)Commented:
Having your mail handled by O365 doesnt necessarily mean that the domain is 'hosted' with O365, you are most likely able to add the PTR via the domain registrar.

If it's actually hosted by O365, you can't do anything about it. The recipient's side should add it to their whitelist instead. You can open a case with O365 support, but I'm almost certain what the answer will be (for example, this recent thread: http://answers.microsoft.com/en-us/msoffice/forum/msoffice_o365admin-mso_domains/domains-being-blocked-due-to-ptr-records-not-being/c5596b6d-72fc-43cb-aee8-8793a9dd870e)
0
 
ptsolutionsincAuthor Commented:
Thanks for the info.  I will contact the recipient to see if they can whitelist the sender's domain as recommended in the link provided.
0
 
ptsolutionsincAuthor Commented:
Thanks for the info.  I will contact the recipient to see if they can whitelist the sender's domain as recommended in the link provided.
0

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now