if reinstalling doesn't work:
Install Arc (PWE's client thing), login to your PWE account THROUGH Arc*, install PWI THROUGH THEIR CLIENT, and play for a min. If you don't have an account you MUST make one.
All steps through Arc are listed as if you are running Arc as an administrator. IF you aren't, this won't work at all, as you won't have elevation permissions to fix the registry and/or install/"upgrade" missing dependencies.
*Windows only (Bootcamp will require other methods!), I CANNOT help Linux/Mac OS users, as I have essentially 0 knowledge of those operating systems/distros.
