Discover sender's network in outlook email ?

Question

Is it possible to discover whether the email is sent from within office network or outside ?

Situation: Someone uses generic mail id to send emails to other named users. We want to identify whether the email is sent from within office network or from outside network (using activesync on mobile ) ?

Note: OWA is disabled for the generic id.

Answer 1

Hi @Pushkal Mishra,

From your description you are using Microsoft 365 and Exchange Online.

On Outlook side you can check the message header and copy/paste the header into Microsoft online tool header analyzer to see the mail flow.

Example (you can see this message is sent from an on-premises Exchange server to EXO):

On Exchange side you can access Exchange Admin Center with an Exchange admin account and use message trace to see more information of the sender.

Example:

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