Application not found

I can’t seem to join a game on web browser, it gave me this error:


(And just for the record, this error also pop-up even if there’s no Roblox installed at the moment).
Tried reinstall, clean up roblox files, clear registry, try to launch on RobloxPlayerLauncher:
ภาพ
,but to no avail. I don’t think my internet have problem.