When you're typing away on your computer screen, little is more alarming than watching everything on your screen suddenly turn upside-down. Chances are, however, that this is not a virus or anything dangerous. As you may realize, you probably hit just the wrong combination of keys as you were typing. Don't worry -- your computer is not stuck this way, and you can fix it in just a few seconds by using another sequence of keys.
Press and hold down the "Ctrl" key on your keyboard. Do not release this key until instructed to do so.
Press and hold down the "Alt" key on your keyboard. You should now be holding down both "Ctrl" and "Alt."
Press the up arrow on your keyboard. This should restore your screen to its natural state. You may now release the "Ctrl" and "Alt" keys.
To turn your screen upside-down again, press and hold "Ctrl" and "Alt" and then press the down arrow. You can also turn the screen sideways using the right and left arrows. You can also revert your screen to normal by right-clicking anywhere on your desktop. Select "Screen Resolution" from the list of options that appears. Click "Landscape (flipped)" in the "Orientation" section and then click "Apply."