MIME in Office ATP

[Jlouden91]

Hi all,

I have a customer that is migrating from a 3rd party email gateway solution to Office ATP P2. One thing that has come up that has stumped me is the 3rd party solution is able to block via MIME type, on top of attachment extension. 

I've not found a similar function in office atp, gui or PS. Does it exist? 

Cheers

JohnL 

[#2 · Accepted solution]

It does check based on content, not just on file extension as detailed for example here: https://docs.microsoft.com/en-us/exchange/security-and-compliance/mail-flow-rules/inspect-message-at...

Or check the description of the common attachment types filter feature.

You cannot add custom mime types if that's what you're after, but you can add custom extensions.