GameLauncher says "installation path not found"

I've had this problem for a while for my official-server client (i.e., not tespia). I've always thought that it started happening when I installed Tespia for Chaos. It didn't bother me at all since I always ran the game through the website anyway... until this latest 2x event started and the website was down for like 15 min.

I also don't know what's wrong since I can poke around in the registry and see a key called "ExecPath" (or something like that) in a MapleStory registry folder with the correct installation directory.