Known mail servers that reject attachments
Depending on your system setup, phishing test emails that contain certain types of attachments may be blocked. See below for known mail servers that reject certain attachment types. We recommend using alternate file types when testing your users:
|Mail Server||Type of Attachment Rejected|
|Google Suite||.pdf, .xlsx, All Attachments with Macros (.ppt, .xls, and .doc)|
|Microsoft 365||All Attachments with Macros (.ppt, .xlsx, .xlsx, and .doc)|
This list is not inclusive of all affected attachment types or mail servers and may change over time. Mail client and server rules change often, so your experience with attachment delivery may vary. If you would like to disable attachments with macros from being sent during a phishing campaign, you have the option to do so from the Phishing section of the Account Settings page. For more information, see this article.
Note: Setting up DMI can allow email attachments in these formats to be delivered in Microsoft 365 and Google Workspace. For more information, see our Direct Message Injection (DMI) Configuration Guide.