Prevent launch an application Prevents the user from launching an application from a Tablet PC hardware button. If you enable this policy, applications cannot be launched from a hardware button, and 'Launch an application' is removed from the drop down menu for configuring button actions (in the Tablet PC Control Panel buttons tab). If you disable this policy, applications can be launched from a hardware button. If you do not configure this policy, applications can be launched from a hardware button.

(1) GPO: User Configuration\Administrative Templates\Windows Components\Tablet PC\Hardware Buttons!Prevent launch an application (2) REG: HKEY_CURRENT_USER\SOFTWARE\Policies\Microsoft\TabletPC!PreventButtonApplicationLaunch