Default User Logon Picture to all users in Windows 7 and Vista

restricting users with a predefined user image in the logon window without having a chance to change it ? It is possible in Windows 7 and Windows Vista by setting group policy editor options. The name of the policy which should be edited is User Accounts in Group policy editor and it apply default user log on picture to all users.

This policy setting allows an administrator to standardize the logon pictures for all users on a system to the default user picture. Microsoft tells one application of this policy as it helps a company to standardize the user logon picture. 

If you enable this policy setting, the default user logon picture will display for all users on the system with no customization allowed.

If you disable or do not configure this policy setting, users will be able to customize their logon pictures.