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How can I unblock attachments in MS Outlook using a group policy?

We are using MS Outlook 2003 in a Windows 2000 domain.  MS Office is rolled out using a group policy from an Administrative install.  I want to use a group policy to add the Level1Remove key to all of our workstations loaded with MS Office, so that I can automate the unblocking of certain attachment types.  Any ideas on how I can accomplish this task?

Thanks, Joe
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Serena HsiMarketing ConsultantCommented:
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.
1. On the Exchange computer, log on by using the Exchange administrator account, and then start Registry Editor.
2. Locate and then click the following registry subkey:
3. On the Edit menu, point to New, and then click DWORD Value.
4. Type DisableAttachments for the name of the DWORD value, and then press ENTER.
5. Right-click the DisableAttachments DWORD value, and then click Modify.
6. Under Base, click Decimal.
7. In the Value data box, type one of the following numbers:• To permit all attachments, type 0.
• To permit no attachments, type 1.
• To permit attachments from back-end servers only, type 2.
8. Click OK.
9. Open a command prompt, type net stop w3svc, and then press ENTER.
10. After the services stop, type net start w3svc, and then press ENTER.

Customize attachment blocking in Outlook 2000 SP3

The "hot new feature" in SP3 is the ability for Outlook 2000 users to customize the attachment blocking that Microsoft added in SP2, with the same documented registry entry that Outlook 2002 uses. As always, when making a change to the registry, make a backup first. Then follow these steps:

Outlook 2002 and Outlook 2000 SP3 (but not Outlook 98 or earlier Outlook 2000 versions) allow the user to use a registry key to open up access to blocked attachments. (Always make a backup before editing the registry.) To use this key:

1.      Run Regedit, and go to this key:


(Note that the key for Outlook 2002 uses 10.0 instead of 9.0.)

2.      Under that key, add a new string value named Level1Remove.

3.      For the value for Level1Remove, enter a semicolon-delimited list of file extensions. For example, entering this:


would unblock Microsoft Access files and Internet shortcuts.
Adding a file type to the Level1Remove value moves it to Level 2, which will still require you to save the file to disk before opening it. End users cannot remove a file type from Level 2. That is possible only for Exchange administrators using the security customization tool from the Office Resource Kit.
Darn, sorry just read that you are using Outlook 2003. I misread your query. However, the above should work for Outlook 2003 - the key you want is HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\Security

Also, if you don't like to edit the registry youself see:
DetachOL - http://mcdev.com/programs.php?page=DetachOL
"Standalone utility to change the list of blocked file attachments according to the level of risk you're willing to take. Works with Outlook 2000, 2002, and 2003. Free,  donations accepted."

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