1. Exit Outlook if it is running.
2. Click Start, click Run, type regedit, and then click OK.
3. Verify that the following registry key for your version of Outlook exists. If it does, go to step 5.
Microsoft Office Outlook 2007
HKEY_CURRENT_USERSoftwareMicrosoftOffice12.0OutlookSecurity
Microsoft Office Outlook 2003
HKEY_CURRENT_USERSoftwareMicrosoftOffice11.0OutlookSecurity
Microsoft Outlook 2002
HKEY_CURRENT_USERSoftwareMicrosoftOffice10.0OutlookSecurity
Microsoft Outlook 2000
HKEY_CURRENT_USERSoftwareMicrosoftOffice9.0OutlookSecurity
If the registry key does not exist, create it. To create the registry key, follow these steps:a. Locate and then click the following registry key:
HKEY_CURRENT_USERSoftwareMicrosoft
b. Click the Edit menu, click New, and then click Key.
c. Type Office, and then press ENTER.
d. Click the Edit menu, click New, and then click Key.
e. For Outlook 2007, type 12.0, and then press ENTER
For Outlook 2003, type 11.0, and then press ENTER
For Outlook 2002, type 10.0, and then press ENTER
For Outlook 2000, type 9.0, and then press ENTER
f. Click the Edit menu, click New, and then click Key.
g. Type Outlook, and then press ENTER.
h. Click the Edit menu, click New, and then click Key.
i. Type Security, and then press ENTER.
4. Click the Edit menu, click New, and then click String Value.
5. Type the following name for the new value:
Level1Remove
6. Press ENTER.
7. Right-click the new string value name, and then click Modify.
8. Type the file name extension of the file type that you want to open in Outlook. For example:
.exe
To specify multiple file types, use the following format:
.exe;.com
9. Click OK.
10. Exit Registry Editor.
11. Restart your computer.
When you start Outlook, you can open the file types that you specified in the registry.