[Twisted-Python] problem installing twisted on Windows 2000 Professional

[John Benson]

I'm running Python 2.3 on Windows 2000 version 5.00.2195 Service Pack 4 and
having trouble running the Twisted-1.1.0.win32-py2.3.exe installation.

I downloaded the .exe to a local folder, got to the Install button, clicked
on it and while the "Saving uninstall information" message was displayed but
before the progress bar showed any progress, I got a Setup message box
saying "CreateFile failed; code 5. Access is denied"

Can anyone tell me what code 5 means?

I've got 112 MB left on the C: drive, I hope that's not the problem.