Understanding when an attachment is blocked while sending an email


Introduction

This article describes why a user may receive the message, "Exchange Online Protection replaced the attachment with this text message. The original file contained error and was deleted.", when checking email with their Virginia Tech Exchange Online account.

Explanation

 

On the Virginia Tech Exchange Online server, all attachments with the following extensions will be blocked (This is a shortened list. Please reference this support page for a comprehensive list of file types.), whether they actually contain a virus or not: