escape key problem

after rendering a scene with F12, my escape key no longer takes me back to the 3D screen. I’ve switched out the keyboard so that’s not the problem. Any ideas?

Some thoughts:
Does Esc work for other functions in Blender?
Also make sure your mouse cursor is in the viewport containing the render when you Esc.
Are you rendering into the UV/Image editor by chance?

no, esc doesn’t work for other functions, yes the cursor is in the viewport, and yes I’m rendering into the UV image editor. The problem didn’t occur until I started UV mapping and rendering the result.

[F12] renders
[F11] switches escapes the render window back to whatever it was before. (with your mouse in the window I think).
The UV editor window sometimes carries a pic of the last render, the IMG list will manipulate that (switch, delete, or use to UV map, etc.)
When you use [P] to enter the game engine [escape] will stop the game engine.