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Undoing The Ill-Conceived Microsoft "Security Update" That Blocks Attachments In Outlook. 

Outlook 2000 or XP (Full Version)

To undo the blocking only requires a couple of entries into the Windows registry file.  Click Here to read this fix directly from my website into your Windows registry.  You should get a prompt like this: 

Choose to Open the file rather than Save it (unless you want to save this fix to apply to several computers).  Once this entry is read into the Windows registry, Outlook will allow you to open and save .EXE attachments normally.  Details on what this does below.   Note that this fix is for the full version of Outlook. The fix  for Outlook Express is different, and is discussed below

In March 2004, Microsoft released a free "Security Update" CD-ROM  for all versions of Windows.  One of the issues this CD addressed was the endless stream of viruses and worms that exploit  flaws in the Outlook and Outlook Express email programs.   In a panic response to the problem, Microsoft took the draconian approach of totally disabling the ability of Outlook to receive numerous types of attached files.  

If you receive an email in Outlook, (after installing the "Security Update", or Windows 2000 Service Pack 4, or Windows XP Service Pack ),  with one of the file types listed below attached, you will discover that you can't open it or "Save As..".  It becomes totally imprisoned in Outlook.   

Notably, this inane "security fix" makes it  impossible to receive any files with the .EXE extension. This includes program installers and updaters, self-extracting ZIP files (ZIP files that unpack themselves without the need for a copy of the unzip program on the recipient's machine), Intuit's "E-Organizer" smart data collection forms, Winfax-generated self-viewing fax-by-email attachments, Omniform self-filling self-mailing forms, and others.  

Reversing this extreme measure only requires entering a line or two into the Windows registry. The link above automates this process. This way you avoid the risky process of hand-editing the registry file.  If you prefer not to run something directly from an unknown website, you can create the file locally on your machine and run it yourself:

After you have saved this file, locate it on your hard disk and double-click it. Windows will ask "Are you sure you wish to add the information to the registry?"  Click Yes and it's done!  Note that the registry entries as shown  fix the problem for both Outlook 9.0 a.ka. Outlook 2000 (Part of MS Office 2000) and Outlook 10.0 a.k.a. Outlook XP  (Part of MS Office XP) 

Windows Registry Editor Version 5.00



You can "liberate" more than one file type if needed. For example you could include DOS batch files and BASIC program files as well by entering  .exe; .bat; .bas  etc. Note that the file types are separated by semicolons ( ; ).   The list below, of file types affected, is extracted from the Microsoft website "Knowledge Base" article that deals with this problem:  

Note that MS Word document files (type .DOC) are not included despite the fact that Word macros are a favorite method for virus writers to do their dirty deeds. 

The "unsafe" category represents any extension that may have script or code associated with it. You cannot open any attachment with an "unsafe" extension if you use a version of Outlook that has the security patch applied to it. The following list contains attachments that are considered "unsafe". 

Extension File type


.ade Microsoft Access project extension

.adp Microsoft Access project

.asx Windows Media Audio / Video

.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

.mda Microsoft Access add-in program

.mdb Microsoft Access program

.mde Microsoft Access MDE database

.mdt Microsoft Access workgroup information

.mdw Microsoft Access workgroup information

.mdz Microsoft Access wizard program

.msc Microsoft Common Console document

.msi Microsoft Windows Installer package

.msp Microsoft Windows Installer patch

.mst Microsoft Windows Installer transform; Microsoft Visual Test source file

.ops Office XP settings

.pcd Photo CD image; Microsoft Visual compiled script

.pif Shortcut to MS-DOS program

.prf Microsoft Outlook profile settings

.reg Registration entries

.scf Windows Explorer command

.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


Outlook Express

These two web pages, found by searching for "Can't open attachments in Outlook" in Google,  explain how to "fix" Outlook Express:





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