How to find if a mail was sent from Outlook desktop ( laptop or mobile application ) or Outlook web?

Hi,

Sorry, I tried to send a mail from both Outlook desktop as well as Outlook web, however, in the message traces or the header, I ma not able to find any of the above mentioned which indicates the specific application used to send the mail.

Can you please perform a test from your end and let me know how it is visible in your end along with screenshots ? This will help to find out what I am missing.

Regards,

Nebu Thomas Mathew

View internet message headers in Outlook - Microsoft Support

Find and fix email delivery issues as a Microsoft 365 for business admin - Exchange | Microsoft Learn

Message trace in the new EAC in Exchange Online | Microsoft Learn

As an admin, you can use email headers and message traces to determine if an email was sent from Outlook on the web or Outlook desktop (laptop or mobile app). Message headers provide technical details about the message, including the client software used to compose it. Message traces allow you to track the path of an email through the organization, including the client and device used by the sender. Using Message Headers:1. View Internet Headers: In Outlook, open the email and go to File > Properties > Internet Headers. 2. Examine Headers: Look for headers like "X-Mailer" or "User-Agent" which may indicate the client software used. For example, "Outlook on the web" or "Outlook Mobile" might be visible.Using Message Traces:1. 1. Access Exchange Admin Center (EAC): Log in to the Microsoft 365 admin center and navigate to the Exchange Admin Center. 2. 2. Run Message Trace: Go to Mail Flow and click on Message Trace. 3. 3. Filter by Sender and Time: Specify the sender and recipient, and the date range for the email in question. 4. 4. Analyze Details: The message trace will show the status of the message and the device or client used by the sender. You can also see the IP address of the device.Additional Notes:

• Outlook Mobile: While the headers might not explicitly state "Outlook Mobile", you can often infer it based on the IP address, especially if the IP address belongs to a cellular carrier.
• Web-based Email: If an email is sent from a web-based email service (like Gmail, Yahoo Mail, etc.), the headers might not provide much information about the specific device used.
• Email Signature: If the sender uses a signature that indicates the device or application used, that can also be helpful. By using these methods, you can effectively determine whether an email was sent from Outlook on the web or Outlook desktop.

Hi,

Were you able to test this from your end and check please ?

You can try to send a mail from Outlook desktop, Outlook mobile and Outlook web. It would be really helpful if you could demonstrate from your end along with supporting screenshots

Regards,

Nebu Thomas Mathew