Dual monitor settings don't allow left or right positioning.

[acroposthion]

Running KDE on Mint, plugging a monitor into my netbook. In the KDE display settings, I have no problems positioning one monitor above or below the other, but it fails when I try to put one to the left or right. The screens go black, I can see my mouse cursor and can move it left and right between monitors, but the selection times out and reverts to previous setting. What gives?

[Orbmiser]

"can move it left and right between monitors, but the selection times out and reverts to previous setting. What gives?"

May be black because no wallpaper assigned to them? Guessing but if you can see and move cursor across both then maybe it's working just without wallpaper?
.

[acroposthion]

May be black because no wallpaper assigned to them?

No no, when you change the settings it asks you if you want to accept and starts a timer, when the timer runs out it reverts back incase it didn't work.

This is a case where it doesn't work. I see nothing but the mouse until it reverts.

[Orbmiser]

Yes that is how it is suppose to work. If you accept the settings than will use that as default.

What I was pointing out just because the screens are black doesn't necessarily mean they aren't working. It may be they need new wallpaper assigned to the screens. As you say you can see and use the mouse during those 30seconds?
.

[acroposthion]

I don't have black wallpaper. Again, the other settings work, I know what I'm supposed to see. It's trying to set it left and right, but fails somewhere.