As video tutorial:
Go to C:\ProgramData\Microsoft\Windows
Right click folder "SystemData", "Properties", take ownership, and give full access right to yourself AND SYSTEM. If you forget SYSTEM you may get a blank pre-login screen. Windows will correct the rights upon next reboot.
then go on to C:\ProgramData\Microsoft\Windows\SystemData\S-1-5-18\ReadOnly\LockScreen_Z
There are the "cached" backgound images. Right click each (usually only one), give yourself full access rights, and then delete it.
Then go to C:\Windows\Web\Screen
The img100.jpg is the one Windows 8.1 uses as template to create the background. Take ownership of the file, and rename it, I used the name img100x.jpg. I don't recommend deleting it.
Copy your own img100.jpg in there. It should be .jpg, 1920x1200.
For Windows 8 it may work the same way, although the Seattle needle (listed as img101.png in Windows 8.1) is used, can someone confirm changing the same way for Windows 8 (replace it with a .png to be on the safe side)?
Special note: Please do NOT mix it up with the LOCK screen! See http://social.technet.microsoft.com/Forums/windows/en-US/82e7ae0f-1b6e-4d04-ae05-8278911af3e2/changing-the-prelogin-screen-background-picture?forum=w8itprogeneral as example how many so called MS-professionals don't get it what it is about.
- Changed type kelvin_hsuMicrosoft contingent staff, Moderator Monday, November 04, 2013 3:15 AM a share article
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