For no apparent reason, when I booted my Mac Mini up this morning, only one of my two monitors was recognized. Not a problem, right? I went to system preferences : Display and put the other one in. But for the same non-reason, the left monitor was on the right and the right one was on the left. So I fixed that as well. Problem is this: It has made the wrong monitor my primary. I tried to use my machine like this, but I'm old and a creature of habit. I can't find anything in Display to change the primary monitor on a dual-monitor system. Help, please!