Can anyone help me?

When I press the button to enable a gizmos ( W, E or 2) nothing happens.

I can't find the problem, but I think I have accidentaly changed a setting

Sometimes the gizmo is way off your viewing area. Zoom out and see if you can find it.

I had this problem. Change your gizmo scaling, it is a setting under movement in the render window properties. Mine was set to zero (for some reason).