This policy setting allows you to prevent users from resizing the taskbar.If you enable this policy setting users are not be able to resize their taskbar.If you disable or do not configure this policy setting users are able to resize their taskbar unless prevented by another setting.
Policy path:
Start Menu and Taskbar
Scope:
User
Supported on:
At least Windows Vista
Registry settings:
HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer!TaskbarNoResize
Filename:
Taskbar.admx