The Sign Out screen is stored in:
Lock Screen Default Background Image - Change in Windows 8
You need to turn on the Show Files and Folders option from Folders Options in order to see it.
Here's how to change the sign out screen:
- go to folder C:\ProgramData\Microsoft\Windows
Right click on SystemData ->Properies->Security->Advanced->Change
- Enter your user name (You must be in Administrators group), then click on Check Names->OK
- Place a tick on "Replace owner on subcontainers and objects", click Apply ->OK, Yes->OK->OK->OK
Go to C:\ProgramData\Microsoft\Windows\SystemData\S-1-5-18\ReadOnly\LockScreen_Z
You will see 2 images of the Seattle Space needle in this folder, To view these 2 images.
- Right click on it->Properties->Securities->Edit->Add
- Enter your user name, Click on Check Names->OK->OK->OK
Replace these 2 images with whatever images you want, make sure they have the same names and resolution as shown in LockScreen_Z.
IMPORTANT: After swapping the images, Right click on image->Properties->Securities->Edit
Make sure SYSTEM is in the user list with permission shown below:
(If SYSTEM is not in the list, you have to add it to the list using the 2 steps above)
Sign out, you should see the new Image.