0017: only works as administrator on Win2000

I recently upgraded to Arduino 0017 on my Win2000. It worked fine for a while, but now when I attempt to start it, it always takes a long time and then gives an error message:

An error occurred while starting the application.
Cannot create a file when that file already exists.

...and nothing else, but I have to kill a javaw.exe instance via task manager.
I noticed that it starts OK if I run it as an administrator, but Arduino 0012 didn't (and still doesn't) need that. Is there a way round this?

Solved, I guess.

When running as administrator, I noticed that the preferences dialog hinted that I could find more options at
c:\Documents and Settings\Administrator\Application Data\Arduino\preferences.txt.

I deleted that file from under my normal user account (not Administrator as above) and now Arduino starts and runs even as a normal user. Still wish it would remember the sketch I last had open, though...