My friend who has only recently downloaded blender has come across a workspace issue. He said he accidentally pressed a button and it has entirely changed his user interface/ Workspace. He can't open, save or do anything with the change.
This is a full window image!
press ShiftSpace or CtrlUp Arrow or CtrlDown Arrowto exit full screen, or go to view->Toggle full screen
It seems he entered Rendered Viewport Shading mode; to close it press Shift + Z, while your mouse is over the 3D View, or go to the 3D View header (on the bottom, above the Timeline) and on the right side to where it says Object Mode, press the button; a list of shading modes will apear, where you can select Solid for the default one.
