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Enable the My Computer Security Zone
http://www.vistaarticles.com/articles/130/1/Enable-the-My-Computer-Security-Zone
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Published on 11/23/2006
 
The My Computer security zone contains settings for how Windows and Internet Explorer manage unsigned controls.

Enable the My Computer Security Zone

The My Computer security zone contains settings for how Windows and Internet Explorer manage unsigned controls. This security zone is hidden by default on the Security tab in the Internet Options dialog box. This article describes how to to view and modify the settings for the My Computer security zone by modifying a registry key.
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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.

The Flags value in the following registry key determines whether you can view the My Computer security zone on the Security tab in the Internet Options dialog box:
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\0
The Flags value is a DWORD value. Setting the data value of the Flags value to 47 (in hexadecimal) causes the My Computer security zone to be displayed. Setting the data value of the Flags value to 21 (in hexadecimal) causes the My Computer security zone to be hidden.