Posted June 07, 2017
high rated

I can run Oblivion.exe directly, but cannot run initial setup or customize things like resoltuion.
Any idea WTF is causing this? I've had Oblivion on Steam for years and I've never seen this issue before.
You can fix this by manually adding / editing the registry key:
open regedit.exe
go to (64bit):
HKEY_LOCAL_MACHINE\Software\Wow6432Node\Bethesda Softworks\Oblivion
or (32bit)
HKEY_LOCAL_MACHINE\Software\Bethesda Softworks\Oblivion
creating new String value named Installed Path and putting your game root folder there.
I posted an example for Fallout here:
https://www.gog.com/forum/fallout_series/cant_change_graphic_settings_fallout_new_vegas_appears_to_not_be_installed/post4