A. IE 6 contains a hard-coded list of unsafe files in the shdocvw.dll file. IE 6 uses the unsafe-file list to prevent you from accidentally opening a file type that might cause problems on your computer.

The complete list of unsafe extensions is

  • .ad
  • .adp
  • .asp
  • .bas
  • .bat
  • .chm
  • .cmd
  • .com
  • .cpl
  • .crt
  • .exe
  • .hlp
  • .hta
  • .inf
  • .ins
  • .isp
  • .js
  • .jse
  • .lnk
  • .mdb
  • .mde
  • .msc
  • .msi
  • .msp
  • .mst
  • .pcd
  • .pif
  • .reg
  • .scr
  • .sct
  • .shb
  • .shs
  • .url
  • .vb
  • .vbe
  • .vbs
  • .vsd
  • .vss
  • .vst
  • .vsw
  • .ws
  • .wsc
  • .wsf
  • .wsh

To add file extensions to the unsafe-file list, perform the following steps:

  1. Start the registry editor (regedit.exe).
  2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\UnsafeFiles\Include (if this registry value doesn't exist, you'll need to create it).
  3. From the Edit menu, select New, Key.
  4. Enter a name of the extension you want to add (e.g., enter .txt as HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\UnsafeFiles\Include\.txt).
  5. Close the registry editor.

To establish exceptions to the core product's unsafe-file list, perform the following steps:

  1. Start the registry editor (regedit.exe).
  2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\UnsafeFiles\Exclude (if this registry value doesn't exist, you'll need to create it).
  3. From the Edit menu, select New, Key.
  4. Enter the name of the extension you want to exclude (e.g., enter .exe as HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\UnsafeFiles\Exclude\.exe).
  5. Close the registry editor.

If you remove the registry entries, Windows will restore the IE 6 unsafe-file list to its default values.