Hi Barkly,
Thank you for posting in the in the Microsoft community. We are happy to assist.
Based on the information you have shared with us; I look like you are getting a notification email from message center that looks like was someone trying to impersonate it.
To fully understand the scenario, I would like to ask some questions to narrow down the situation work toward the resolution.
Please could you share with us the following information:
- Kindly share with us extended message trace of that email ,Message trace in the new EAC in Exchange Online | Microsoft Learn
to run a message trace in the Microsoft 365 admin center, follow these steps:
- Sign in to the Exchange admin center:
- Navigate to Mail flow:
- Click on Message trace.
- Select + Start a trace.
- Configure your trace:
- Choose extended report
- Click Search to run the trace.
- You can view the results directly or download them as a CSV file for detailed analysis
- Kindly share with us message header of that email
Outlook Desktop App:
- Double click on the email.
- Click on File > Properties.
- In the Properties window, you'll see the Internet headers box at the bottom. This contains the full message header.
This will help us to identify exact sender so that you can block him and stop those threatening emails.
Please note that my initial response may not address your current situation immediately. However, with your help and more detailed information, we can work together to find a direction specific to your current situation.
Note: To protect sensitive information, please share with use the above requested screenshot information in "View Private messages".
Here are the steps to open "View private messages":
To view private messaging options> Sign in to Microsoft Community, use the email account where you posted this thread information to Microsoft Community, > click your profile picture in the top right, > select the My Profile option.
If you have any other questions or need further assistance, feel free to ask!