How to Allow Specific Attachments in Outlook 2003

By default Outlook blocks several types of attachments for security reasons. There are two levels of attachment security in Microsoft Outlook 2003. Access to Level 1 files is blocked and you can’t changed that. When you receive an attachment with a Level 2 file type, you will be prompted to save the file to your hard disk. There are no Level 2 files by default but you can add or remove Level 2 type files if you are an administrator. There are dozens of Level 1 type files. For a list of Level 1 file types that are blocked by Outlook, click here.

If you wish to allow certain types of attachments in Outlook 2003, e.g. URLs, you can modify the registry as described below.

1. Clik, Start, Run, and type regedit.exe to start the registry editor.
2. Go to HKEY_CURRENT_USER\Software\Microsoft\Office\Your Version Number\Outlook\Security. The version number will be something like 10.0 or 11.0, depending on your version.
3. Click Edit, New, String Value.
4. For Value name type Level1Remove and press Enter.
5. Double-click the new entry and set the Value data to a list of extensions seperated by semicolon that you want to allow. For example, if you want to allow URLs, EXE and VBS files, enter url;exe;vbs in lowercase. Do not enter a period before file types.
5. Restart Outlook for the changes to take effect.