Windows 2008 R2 Change Default wallpaper

When a user first logs onto a windows 2008 R2 server they see the windows 2008 wallpaper. 

This occurs even if a wallpaper is set with GPO. This due to the GPO running to late in the logon process to change the wallpaper. 

This gives a very poor first logon experience to users. (along with loads of other rubbish 2008 settings that are very hard to change)

A workaround for this is to edit the windows default wallpaper.

C:\Windows\Web\Wallpaper\Windows\img0.jpg

The file has trustedinstaller settings so you will need to take ownership of the file in order to edit it,