Hello Jérmone and Aaron, In February I had to update my Mac with HighSierra and run into the problem which is described here. I installed the update in Ticket 1652, (TaskCoach 1.4.3.7969). Unfortunately this didn´t help. When starting TaskCoach I get the a message (see down). The Tasks are shown, but when I try to open one task or sort a colum, the Mac (!) will be restarted at once. Currently, I cannot work with TaskCoach on the Mac. The temporary workaround is using a second (older) computer with...