Had the same issue, HoM titles got revoked (has happened before, logging into GW1 fixes it) but my computer couldn't locate the game when I tried launching it from my taskbar. I could open it from the Guild Wars folder, but that screwed up my settings somehow when the game got launched. Attempting an uninstall and using the "reinstall Guild Wars to this location" seems to have fixed the issue (and my settings). Hope this helps.