I went out yesterday to use my GPS device - actually to re-charge the battery - but also to make sure that it was still working correctly. I went through the different nav programs. They all worked fine except for XT. For some reason, it went back to the program being installed but it was with the four choices and didn't go straight to the license acceptance instead so it wouldn't work. When I got it home, I looked and for some strange reason the SW.UNL was gone from the program on the SD card. So I re-created it and then all was fine again. Stange