Unsafe File Types

Microsoft has deemed email attachments with certain extensions to be unsafe. The SSU email server filters unsafe attachments from messages, and a notice that the attachment has been removed is inserted in the message.

SSU email users have seen an increasing number of viruses that use email to spread. This problem is not expected to diminish in the near future.

If you need to send a file attachment with one of these extensions, you can rename the file so that it no longer has the original extension. In the message body you can include instructions for renaming the file back to its original name.

General Advice on File Attachments in Email Messages

Microsoft classifies the following extensions as unsafe.

Possible Unsafe Extensions
Extension Type of File
.ade Microsoft Access project extension
.adp Microsoft Access project
.bas Microsoft Visual Basic class module
.bat Batch file
.chm Compiled HTML Help file
.cmd Microsoft Windows NT Command script
.com Microsoft MS-DOS program
.cpl Control Panel extension
.crt Security certificate
.exe Program
.hlp Help file
.hta HTML program
.inf Setup Information
.ins Internet Naming Service
.isp Internet Communication settings
.js JScript file
.jse Jscript Encoded Script file
.lnk Shortcut
.mdb Microsoft Access program
.mde Microsoft Access MDE database
.msc Microsoft Common Console document
.msi Microsoft Windows Installer package
.msp Microsoft Windows Installer patch
.mst Microsoft Visual Test source files
.pcd Photo CD image, Microsoft Visual compiled script
.pif Shortcut to MS-DOS program
.reg Registration entries
.scr Screen saver
.sct Windows Script Component
.shb Shell Scrap object
.shs Shell Scrap object
.url Internet shortcut
.vb VBScript file
.vbe VBScript Encoded script file
.vbs VBScript file
.wsc Windows Script Component
.wsf Windows Script file
.wsh Windows Script Host Settings file