Invisible control windows?

[ADM56]

I'm running CS6 Photoshop on Mac El Capitan.

When I try to resize an image using "Image Size" no window controls are opening. At the same time Photoshop behaves as if the window is open in that all operations are frozen unless I hit the return. This "invisible" control window problem is occurring with any operation I try that involves changing values.

[Sahil.Chawla]

Hi ADM,

By any chance are you using a secondary screen? because I think the Image size window might be opening on another screen.

Regards,

Sahil

[ADM56]

I'm only using one iMac. Single screen. Is there a setting I should look for that might be causing the app to believe I'm working  screens?