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

Posted on 2005-04-07
Last Modified: 2008-01-09
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
Question by:rudejoe
    LVL 16

    Expert Comment

    by:Serena Hsi
    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.;%5Bln%5D;830827#10
    LVL 8

    Accepted Solution

    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.
    LVL 8

    Expert Comment

    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 -
    "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."

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    How to run any project with ease

    Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
    - Combine task lists, docs, spreadsheets, and chat in one
    - View and edit from mobile/offline
    - Cut down on emails

    In case Office 2010 has not been deployed in your environment, this article may be quite useful. In our office, we wanted a way to deploy Microsoft Office Professional Plus 2010 through an automated batch file via logon script. This article is docum…
    My experience with Windows 10 over a one year period and suggestions for smooth operation
    The view will learn how to download and install SIMTOOLS and FORMLIST into Excel, how to use SIMTOOLS to generate a Monte Carlo simulation of 30 sales calls, and how to calculate the conditional probability based on the results of the Monte Carlo …
    Learn how to create and modify your own paragraph styles in Microsoft Word. This can be helpful when wanting to make consistently referenced styles throughout a document or template.

    758 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    9 Experts available now in Live!

    Get 1:1 Help Now