Public folders not receiving email and Office365 Admin Centers are extremely slow

Occasional Visitor

 Set up O365 for the company after on-prem exchange died a fiery and painful death. They have a number of public folders that receive email. They all bounce externally saying: 550 5.4.1 []: Recipient address rejected: Access denied. I go through the web console and make sure all senders can send and no senders are blocked, I log in through powershell and give anonymous createitem access, you name it. They have unlimited size. I plan on migrating 80gigs of public folders.


O365 support blames me for using Barracuda for my MX records. I say that is not the case, but I take it off and test, same issue. Then they want me to make them shared folders, but that doesn't work with how I am migrating the public folders. I asked for it to be escalated, but have yet to hear a peep in 8 hours. I kept getting sent support articles telling me how to share public folders, but we went through ALL of them in painstakingly long fashion while the guy was remoted into my machine for 3 hours last night. They are set up correctly for the umpteenth time. It's like the guy is afraid to escalate the issue.


Also, the admin centers are just PAINFULLY slow. I'm using Chrome (latest) on a 6c/12t Core i7 with 32GB, all solid state hard drives, with 500Mbps/50Mbps internet, full gigabit throughout. My machine and my internet are essentially idling. Is their any way in the world to speed this up?


EDIT #1: I created a public folder (finally, only took 29 minutes), still get the same delivery error.

2 Replies

Hey @Michael Leone,


No idea if this is the root cause but worth testing out. I had all sorts of issues with Public folders for a client when I was doing a hybrid migration from 2010, up to O365, as with PF's I had to first go to 2016.


Is your domain set to Internal Relay, or Authoritative?


When the domain type is set to Authoritative, Directory Based Edge Blocking allows any SMTP address that has been added to the service, except for mail-enabled public folders.

So if your domain is sitting as authoritative it can cause problems. If it is, try setting it to Internal Relay, and give it some time to propagate, then test again.

Again, not sure this will help, but that was my problem.



DBEB would be my primary suspect here as well, so +1 to what Adam said above. Just wanted to add this blog article with more details, especially if you are in a hybrid config:


In addition, make sure to run a (detailed) message trace to get more details. If the message is not visible at all there, it's another hint that DBEB might be causing this.