This policy setting allows you to turn off taskbar thumbnails.If you enable this policy setting the taskbar thumbnails are not displayed and the system uses standard text for the tooltips.If you disable or do not configure this policy setting the taskbar thumbnails are displayed.
Policy path:
Start Menu and Taskbar
Scope:
User
Supported on:
Windows Vista only
Registry settings:
HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer!TaskbarNoThumbnail
Filename:
Taskbar.admx