A few days ago I downloaded and ran the offline installer, then the universal installer. GSX came back and ran fine for a few flights. Then suddenly starting a flight I called up the GSX menu to dock the jetway and begin loading the plane. GSX stopped as soon as the pylons appeared, and I could not bring up the GSX menu. I ran the universal installer again and did another flight with the same issue, no GSX function at all. I flew into LAX and it was missing. Once again I ran the offline installer, then the universal installer to update. LAX is back, but GSX disappeared again as soon as I called for the jetway.