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Attachment blocks

In order to protect our users against unknown viruses, we block attachments that have any of the filename extensions listed below.  Emails that contain any such attachments will be rejected, and an error message will be returned to the sender.

This list is based on the "dangerous attachment types" blocked by Microsoft Outlook.

More details about our email scanner.

In this table, [] means any of the enclosed letters, ()? indicates an optional suffix, and []? means an optional letter.

.ad[ep] Microsoft Access file
.app executable application
.asp Microsoft Active Server Page
.bas BASIC source code
.bat Microsoft command script
.cer security certificate
.chm compiled HTML help
.cmd executable command
.cnt Microsoft Help Workshop Application
.com executable command
.cpl Microsoft Windows control panel
.crt security certificate
.der DER-encoded X.509 certificate
.dot Microsoft Word template
.exe executable program
.fxp FoxPro code
.gadget Microsoft Windows Vista gadget
.grp Microsoft program group
.hlp Microsoft Windows help file
.hta hypertext application
.hpj AppWizard Help project
.inf information / setup file
.ins Internet communications settings
.isp Internet service provider settings
.its Internet document set
.jnlp Java Network Launch Protocol file
.jse? JavaScript code
.lnk Microsoft Windows shortcut
.ma[dfgmqrstvw] Microsoft Access
.mau Media Attachment Unit
.mcf Media Container Format
.md[abetwz] Microsoft Access
.msc Microsoft management console snap-in
.msh[12]?(xml)? Microsoft Shell file
.ms[ip] Microsoft Windows installer file
.mst Microsoft Windows SDK setup script
.ops Microsoft Office profile settings
.osd Open Software Description
.pcd Microsoft Visual Test script
.pif Microsoft Windows program information file
.plg Developer Studio Build Log
.prf Microsoft Windows system file
.prg executable program
.ps[12](xml)? Windows Powershell
.psc[12] Windows Powershell
.pst Exchange/Outlook store
.reg registry data
.scf Microsoft Windows Explorer command
.scr Microsoft Windows screen saver
.sct Microsoft Windows script component
.shb Microsoft Windows shortcut into a document
.shs Microsoft Windows scrap object
.tmp Temporary file
.url Internet location
.vb[eps]? Microsoft Visual Basic code
.vsmacros Microsoft Visual Studio macro
.vs[stw] Microsoft Visio file
.ws[cfh]? Microsoft Windows Script
.xbap Browser Applications
.xll Excel add-in
.ani Microsoft Windows mouse cursor
.cab Microsoft installation archive
.cnf Microsoft SpeedDial configuration
.cur Microsoft Windows mouse cursor
.ico Microsoft Windows icon
.job Microsoft Windows scheduled task
.xnk Microsoft Exchange shortcut
.{long-encoded-string} Microsoft Windows CLSID hidden file type