Cant change User account,Lock Screen in Windows 8

Wednesday

If you are facing Can't change Lock or Background or User Account  problem in Windows 8, just create the Registry key using following steps.

1. Press "WIN+R" key combination to launch RUN dialog box then type regedit and press Enter. It'll open Registry Editor.

2. Navigate to following key

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace

3. Now search for a key {B4FB3F98-C1EA-428d-A78A-D1F5659CBA93} under NameSpace key. If it exists, click on it and in right-side pane, check the value of (Default). It must be set to Other Users

If the key doesn't exist, right-click on NameSpace key and select "New -> Key" option & set the new key name to {B4FB3F98-C1EA-428d-A78A-D1F5659CBA93} and in right side pane change value of Default to Other Users.
  
4. Download this Registry file given below and run it.
Download HERE