I happened to turn ipad from landscape to vertical as it was returning from website to home screen folder and it locked showing folder (with half a dozen icons in it). I tried tapping to return to main home screen, indeed everything I could think of. I pressed home screen button which does nothing, then tried pressing power button, both rapidly and long press, but still nothing. Finally I tried pressing both home button and power button, and the screen cleared to black. I allowed it to rest, but it needed a long press to get it going again,but it was the locked folder that appeared, locked in as much as it wouldn't do anything. The next thing I did was to connect the power and try pressing a few things, still nothing. I am now giving it rest time to see if that has any effect. ps I've now got the locked folder back on screen. If I touch the screen with three fingers, a TV shape with sort of button appears in silhouette and disappears if I three finger touch again, PPS, if I rotate the screen, I can see it rotate, but the locked folder showing website icons, remains static. PPPS It has cleared. I pressed both home button and power button for 10 secs untill the apple logo appeared then released. I suppose there is a name for this?. Is this the correct procedure for a locked screen?