These forums are primarily about programming questions, not Win XP user support.
However, google provided a simple fast answer for this by searching for gina.dll:
See:
http://support.microsoft.com/default...;en-us;Q164486
Winlogon may fail if the third-party Gina.dll file is missing or corrupted
If you haven't been editing or replacing the gina.dll file yourself, you may want to google on it and read some of the other articles that result.
Jim Minatel
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Wiley Technology Publishing
WROX Press
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