Hi, I had this very weird problem for a couple of days.
I have two monitors attached on my DELL T3610 desktop PC running Windows 7 and Matlab 2017a, with an AMD Fire pro graphics card and the AMD Catalyst control center. I usually keep my main desktop on the right monitor but now when I move matlab windows to the left monitor they are not responsive (and partially not visible). Strangely enough, if I move the main desktop to the left monitor then everything works on the left monitor and I can move matlab windows to the right monitor and they are responsive. I do not encounter this problem with any program other than Matlab. This does not seem to be a problem related directly to my left monitor because if I virtually change the position of the monitors and set the desktop on the virtually right monitor (physically left) now windows do not respond on the physically right monitor. I also tried to swap the socket in the graphics card where the monitors are plugged but the problem persists.