The "unsafe" file list is used to prevent you from accidentally opening a file that could cause problems on your computer.

The list is hard coded in the Shdocvw.dll file.

IE6 has added the following file types to the list, making it consistent with Microsoft Office:

.ad  Microsoft Access project extension
.adp Access project
.crt Security certificate
.ins Internet Naming service
.mdb Access program
.mde Access MDE database
.msc Microsoft Common Console document
.msp Microsoft Windows Installer patch
.sct Windows script component
.shb Shell scrap object
.vb  VBScript file
.wsc Windows script component
.wsf Windows script file
.cpl Control Panel extension
.shs Shell scrap object
.vsd Microsoft Visio file type
.vst Visio file type
.vss Visio file type
.vsw Visio file type
The complete list includes the above file types and the following:
.asp
.bas
.bat
.chm
.cmd
.com
.exe
.hlp
.hta
.inf
.isp
.js
.jse
.lnk
.msi
.mst
.pcd
.pif
.reg
.scr
.url
.vbe
.vbs
.ws
.wsh
To add additional file types to the list:

1. Use Regedt32 to navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer.

2. If the UnSafeFiles sub-key is NOT present, use the Edit menu to Add Key name UnSafeFiles.

3. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\UnSafeFiles.

4. If the Include sub-key is NOT present, use the Edit menu to Add Key name Include.

5. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\UnSafeFiles\Include.

6. For each file type that you wish to add, use the Edit menu to Add Key name . Example: To add the .xyz file type, add a sub-key named .xyz.

NOTE: To exclude a built in file type, like .exe, create the .exe sub-key in the following path:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\UnSafeFiles\Exclude.