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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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fire99's avatar
fire99
Copper Contributor
Jul 15, 2023
I created a rule to forward all emails with html attachments to the administrator for approval. That way I can determine if they are legit or not. It works great for us.
  • 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.

       

  • lbergstrome's avatar
    lbergstrome
    Copper Contributor
    Jul 18, 2023

    Oh wow fire99 I bet they love that! :xd:

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