email not received

[Rising Flight]

Hi experts

one of my application(myapp@mydomain.com) has sent an email to external user lets say someuser@somedomain.com

The external users says that he did not receive the email. please help to troubleshoot this issue. what i understand is i need to check two scenarios( the email might be blocked at external user but from my exchange server end i need to make sure there is no issue at my end)

1. did the application sent an email and did he hit my exchange server.

2. If the email hit my exchange did the email go out of my server.

please help me powershell command to troubleshoot.

[#2]

ok

[#3]

You don't mention whether you are using on-prem Exchange or Exchange Online.

Regardless of which Exchange you are using, just go to Exchange Admin center and use Message Trace.

[#4]

hybrid enivronment but the application and mailbox is on premises