ressting the phone
ok. first go to settings then applications then make sure the "unknown sources" box has a tick on it. then
go to your htc desire s and copy this on the address bar of the internet http://db.tt/7XJPQCa
then when its downloaded tap it and install it and overwrite the previous app. hope that works
Help me man.. i have the same youtube apk issue on my desire s... pls do me a favor telling me the detailed solution in fixing it..