This is due to the installation of Microsoft Windows updates, any new software, or Service Pack for IE. Some critical files failed to be copied to the Windows\System32 folder during the installation of any software mentioned or SP1 (including shlwapi.dll and msgina.dll). The Winlogon process is updated by SP1.
When winlogon.exe runs, looks for these dlls, and finds mismatched versions, it fails to execute. As a result, XP fails to load. The msgina.dll file is required by the Winlogon service.
The DLL file is msgina or msgina.dll. The DLL name isWindows NT Logon GINA DLL
Msgina.dll is a module loaded by Winlogon to implement the authentication policy. The file performs all user identification and authentication interactions.