The Default Windows Logon Interface May Not Appear After Installing Third-Party Programs in windows. Also there might be errors with the shutdown screen. Here’s how to restore the fancy windows xp logon screen:
Fix Logon/Restore Welcome Screen:
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This should reset the default GINA in registry. To set it manually, see the following KB article:
The Default Windows Logon Interface May Not Appear After Installing Third-Party Program
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Note that you will need to delete the “GinaDLL” entry rather than assigning a blank data to it.