I've encountered the same issue and already cleared the data cache, restarted computer and tried again (didn't work). I then went and put Origin into R&D mode to see what was what.
Debug Info showed:
Install Check Registry Key:
Missing key-[HKEY_LOCAL_MACHINE\SOFTWARE\EA Games\Need for Speed(TM) Most Wanted\Install Dir]
P.S: I tried to manually add the key but there are no files whatsoever to add it to so the whole directory just isn't existent for some reason.
I don't know if this would have to do with the same problem but this is all I have to offer with the current problem I am experiencing as well.
