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Kiril's avatar
Kiril
Iron Contributor
Mar 23, 2023

How to classify E-Mails with *.html or *.htm attachments as spam?

A tenant is receiving currently an enormous amount of phishing emails with *.html or *.htm attachments. 99% of the e-mail which contain such an attachment are phishing e-mails. What's the best approa...
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alecfunes's avatar
alecfunes
Copper Contributor
Jul 21, 2023

fire99 Creating a rule was my first step, but I only have the "mail has an attachment" condition, and then I couldn´t add a 2nd condition in order to filter type of attachment.

How did you do that?

Thanks in advance!

fire99's avatar
fire99
Copper Contributor
Jul 21, 2023

alecfunes Go to the Exchange Admin Center, Under Mail Flow, Go to Rules.  Here is a screen shot of my rules.  The extensions are one I experimented with that should be blocked (there may be more I should be blocking)

 

 

Hope this helps.  Works great for me.

 

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