I have a user that can send and receive mail internally and externally successfully, except for two external addresses (both in the same domain.) ***NOTE: I have successfully sent mail to these addresses from my account. I have tried to run a delivery report via EAC, but no matter what parameters I select I always get no results. I also tried to run a "report" via powershell using the Get-MessageTrackingLog cmdlet, but I never get results there either. 

If you can send email to the accounts successfully, then it has to be the user/user mailbox at fault.

I would start by removing the addresses from the Auto Complete list that appears when you start to type addresses (press down and then delete). I would also do a test from OWA as well.

Simon.

Hi,

Please check if you have message tracking log enabled by using either the Get-TransportService or the Get-MailboxServer

If it has been enabled, please post the command you used. And what's NDR when sending messages to those two external address?

Best Regards.