KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q259514: XCLN: Modifying the Attachment Security Warning in OL 2K SR-1

Article: Q259514
Product(s): Microsoft Exchange
Version(s): 5.5
Operating System(s): 
Keyword(s): 
Last Modified: 11-JUN-2002

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Outlook 2000 
- Microsoft Exchange Server, version 5.5 
-------------------------------------------------------------------------------

IMPORTANT: This article contains information about modifying the registry. Before you 
modify the registry, make sure to back it up and make sure that you understand how to restore 
the registry if a problem occurs. For information about how to back up, restore, and edit the 
registry, click the following article number to view the article in the Microsoft Knowledge Base:

  Q256986 Description of the Microsoft Windows Registry

SUMMARY
=======

Microsoft Outlook 2000 Service Release 1 (SR-1) provides an attachment security
feature that is designed to increase the security protection for certain types
of e-mail attachments. This feature provides explicit warning language when
attachments are opened, and you are required to save the attachment to the file
system before opening it. This can help you avoid accidentally releasing viruses
that hide in certain file types.

Note: In previous versions of Outlook, this functionality was provided in three
separate patches: one for each version of Outlook.

MORE INFORMATION
================

When you open attachments with file name extensions such as .exe, .bat, .com, or
.cmd, you receive the following warning message:

  Attachment Security Warning

  WARNING!

  The file may contain a virus that can be harmful to your computer. It is
  important to be VERY certain that this file is safe before you open it. You
  must save this file to disk before it can be opened.

  Filename: "file name"
  Type: "file type"

  To save the attachment, click Save to Disk.

Caution: The attachment warning runs for all attachments with executable file
name extensions. It does not detect, or clean a virus from an infected
attachment. If you save a file that has a virus, and then run it from the hard
disk, your computer is still infected. Saving the file is simply an extra
precaution to take when considering the safety of the attached file. You must
still use an updated virus-scanning program to check the file for a possible
virus.

Microsoft Office files, such as .doc, .xls, or .ppt, are not affected by this
patch, and behave just as they did before installing the patch. To control macro
behavior for Office documents, set the security level in the individual Office
program itself.

To Modify the Behavior of the Attachment Security Warning:

WARNING: If you use Registry Editor incorrectly, you may cause serious problems
that may require you to reinstall your operating system. Microsoft cannot
guarantee that you can solve problems that result from using Registry Editor
incorrectly. Use Registry Editor at your own risk.

To either add, or remove file types for the Attachment Security Warning, follow
these steps:

1. Click Start, click Run, type "regedit" (without the quotation marks), and
  then click OK.

2. Locate the following key:

  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\9.0\Outlook\Security

  If the Security key is not present, right-click the Outlook key, point to New
  on the shortcut menu, and then click Key. Type "Security" (without the
  quotation marks) as the name, and then press ENTER.

3. Click to select the Security key, and on the Edit menu, point to New. Click
  String Value, type "AddWarningFileTypes" (without the quotation marks), and
  then press ENTER.

4. Right click AddWarningFileTypes, and then click Modify. Enter the extensions
  of those file types for which you want to receive a warning in the "Value
  data" box. Note that the file extensions should be entered as semicolon- (;)
  delimited strings without using any periods (.).

5. Click the Security key, on the Edit menu, point to New, and then click String
  Value. Type "RemoveWarningFileTypes" (without the quotation marks), and then
  press ENTER.

6. Right-click the RemoveWarningFileTypes value, and then click Modify on the
  shortcut menu. Enter the extensions of those file types for which you do not
  want to receive a warning. Note that the file extensions should be entered as
  semicolon-delimited strings without using any periods.

7. Quit Registry Editor.

NOTE: You must have some string value added to the AddWarningFileTypes key in
order for RemoveWarningFileTypes to work. If necessary create a fake extension
for AddWarningFileTypes, such as <qqq>
For additional information about this feature as used in previous versions of
Outlook, click the article number below to view the article in the Microsoft
Knowledge Base:

  Q235309 Outlook E-mail Attachment Security Update

Additional query words:

======================================================================
Keywords          :  
Technology        : kbOutlookSearch kbExchangeSearch kbExchange550 kbZNotKeyword2 kbOutlook2000Search kbZNotKeyword3
Version           : :5.5
Issue type        : kbhowto

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.