OK. How I said months before I ha have a PC with MU2 and a notebook with Falco. Sometimes on my PC MU2 asks for new activation, I force quit XPLANE and hate activation-xxxx, and after restart it works again. I can't count with MU2.... Now I hate this. I hope 1.5 helps, but tomorrow I can not fly with MU either... 7 of 10 times I can't use it. I AM THE ONLY USER on one PC with mu2: "You, on the other hand, have needed one so many times that it's easy to count on multiple hands." ??? This problem must be solved.