550 5.7.64 Relay Access Denied ATTR36

[null null]

Hello,

I just setup a client with a new Office365 and I am running into problems with inbound email bouncing.

The issue seems to be two problems.

First email are bouncing due to:

"Host or domain name not found. Name service error
    for name=XXXXXX.mail.protection.outlook.com type=AAAA: Host not
    found"

Upon further investigation it looks like XXXXXX.mail.protection.outlook.com DNS is not always resolving.
I tested this with MxToolbox.

Another bounce I'm receiving is 550 5.7.64 Relay Access Denied ATTR36.
Per Microsoft I should should only be getting this if I have connectors configured which I don't.

I have been on the phone with support for hours and so far no luck.
First I was told by support that there is an outage.
Upon looking at the health page the outage was with voicemail not email.
Then I was bounced around between a few technicians until I found one that was able to understand what I was telling them.
He confirmed that he sees the issue (the email he sent me bounced back with the "550 5.7.64 Relay Access Denied ATTR36") and will call me back but so far nothing.

Any assistance would be appreciated.

Thank you,

Avrom

[#2]

Hi 

Could you share your email address so that I can send a test email and investigate further. 

Hope you have already pointed you MX to Office 365 and is your set up Hybrid or On Cloud only.

Thanks

Robin Nishad

[#3]

Hello All,

We are also seeing smtp;550 5.7.64 Relay access denied ATTR36. while sending emails from relay using SMTP IIS server.

Thanks,

Nageswar

[#4]

Hello Avrom,

Normally the  550 5.7.64 Relay Access Denied ATTR36 is related to an invalid cert when trying to relay mail.

As you said an incorrect connector could cause this, but I would more expect something like the other user suggested, where they are attempting to relay the messages from another mail system through O365 and getting the problem.

I have personally seen this when on-prem values get changed (IP address, cert, etc) in a hybrid setup. Are you running a hybrid setup at all? I assume not since you said you have no connectors?

If that is true, and you do not have connectors setup in any way, I am guessing this is an issue on the O365 side, and unfortunately support is probably your best route.

Adam

[#5 · Accepted solution]

Hi,

After a week of calling Microsoft support twice a day they finally fixed it.

They didn't tell me what the issue was.

I guess who ever runs into the same issue will need to do the same.

Thank you,

Avrom

[#6]

Could you pls help us with the ticket number or the troubleshooting steps of it.

I am stuck on the same **bleep** scenario!