Blocked Attachment Types in Outlook

Summary

Learn which attachment types Outlook blocks and how to share those files safely instead.

Body

Learn why Outlook blocks some attachment types, such as .exe files, and how to share those files instead.

Outlook blocks file types that are commonly used to spread malware, including program and script files such as .exe, .bat, .js, and .vbs. For the full list, see Microsoft's Blocked attachments in Outlook.

Need to share one of these files?

Share it from OneDrive or Teams with specific people instead of attaching it. See How To: Share a File Securely from Teams or OneDrive.

Didn't expect the file?

Don't try to get around a blocked attachment from someone you don't know. Report it. See Phishing — Reporting a Phishing Scam or Suspicious Email.

Get help

Submit a request through the Microsoft Office 365 E-mail & Calendar service.

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Details

Details

Article ID: 72355
Created
Wed 2/20/19 8:23 PM
Modified
Sun 10/18/26 7:05 PM
Audience
Employees
Students