where are the web player files installed? 2.5 not updating

I have 2.5 web plugin installed (Win xp), but when I 'update' it, no content runs (after the loading screen), and the log shows it's 2.5f. I uninstalled with control panel, reinstalled from unity3d.com (auto and manual), and it's the same: 2.5f

I just want to nuke the old files. Where are they?

Look in windows/system3d for the ocx, nuke that. run regedit and look for 'unity' and nuke anything that looks like it might be web player related.