In honor of April Fool’s Day, here are 10 computer shortcuts you can use for evil pranking a friend. Why would you need to use these? Let’s say your friend or co-worker steps away from his desk for just a few minutes (to get more coffee or go to the bathroom) and foolishly leaves his computer unlocked.

These shortcuts will allow you to use that small window of time to pull a (somewhat) harmless computer prank that’s not only hilarious, but teaches him the value of locking his computer when he steps away.

NOTE: Humor’s Office is not responsible for any damage (physical or mental) these shortcuts may cause. Also all of these shortcuts were tested on Windows 7 / Office 2007, though will likely work on most versions of Windows / Office.

10 Computer Shortcuts You Can Use for Evil

1. Turn on High Contrast

What It Does: Turns on High Contrast mode on a computer screen.
Level of Evilness: 1 – It just changes the display, which is easily reversed.
How to Do It: Hit Left Alt + Left Shift + PrintScreen.
How to Fix It: Hit the same keys: (Left Alt + Left Shift + PrintScreen).

2. Lock the scrolling in Excel.

What It Does: Changes the behavior of Excel so that when you hit the arrow keys, it changes the view, not the cell selection.
Level of Evilness: 2 – Experts in Excel will quickly know what’s going on, but novices will likely be confused / gradually aggravated.
How to Do It: In Excel, hit Scroll Lock.
How to Fix It: Hit Scroll Lock again.

3. Turn the display upside down.

What It Does: Changes the orientation of the computer display to left, right or upside down.
Level of Evilness: 3 – It might confuse people, but is easy to fix and does no permanent damage.
How to Do It: Hit Ctrl+Alt+DownArrowKey (or Left, Right or Up).
How to Fix It: Ctrl+Alt+UpArrowKey.

4. Turn on Computer Beeps.

What It Does: Turns on “ToggleKeys” which makes the computer beep every time you push a lock key (such as Caps Lock).
Level of Evilness: 4 – It doesn’t do any damage and may take awhile to pay off, but it can certainly be annoying when you don’t know why your computer is beeping.
How to Do It: Hold down the NUM LOCK key for five seconds, then hit Yes.
How to Fix It: How down NUM LOCK for five seconds again.

5. Insert Random Text in Word.

What It Does: Inserts random text into Microsoft Word.
Level of Evilness: 5 – It’s pretty easy to remove to random text from a document, but if you put it in the middle of a 30 page proposal, it may take a while to get noticed.
How to Do It: Enter the following into Word: “=rand(x,y)” where x = the number of paragraphs and y = the number of sentences you want.
How to Fix It: Highlight the random text and hit Delete.

6. Make the keyboard seem broken.

What It Does: Turns on FilterKeys which ignores brief or repeated key strokes.
Level of Evilness: 6 – It’s easy to fix but may take some people a long time to even realize FilterKeys is enabled; in the meantime they’ll think their computer is broken or they don’t know how to type.
How to Do It: Hold the right Shift key for 8 seconds, then hit Yes.
How to Fix It: Hold the right Shift key for 8 seconds.

7. Create a Dummy Desktop.

What It Does: Replaces the desktop background with an image of the old desktop background. If you remove the folder icons, it then seem like the computer is not responding / desktop shortcuts won’t open.
Level of Evilness: 7 – Easy to restore unless you delete all of the shortcuts and empty the recycling bin. Incredibly frustrating while you try to figure it out.
How to Do It: Go to the desktop, hit Ctrl+Prnt Screen. Open Microsoft Paint, hit Ctrl+V to copy the screen capture of the image, save the image. Right click on the image, select “Set as Desktop Background.” WindowsKey + D to go the Desktop, Ctrl+A to select all shortcuts, Delete to delete.
How to Fix It: Restore the shortcuts from the Recycling Bin, reset the Desktop background.

8. Change the capitalization in a word document.

What It Does: Changes the case of the selected words (CAPS, no caps, Proper).
Level of Evilness: 8 – It’s pretty easy to fix (with Ctrl+Z) but could be really annoying for large documents if you save/close the document, especially for anything with a lot of acronyms.
How to Do It: In Microsoft Word, highlight a selection (or the entire document by hitting Ctrl+A), then hit Shift+F3 to cycle through: all caps, no caps, proper case.
How to Fix It: Ctrl+Z is the easiest. If you save the document and then exit, Ctrl+Z won’t help. The next best step is to highlight the section and Shift+F3 to proper case (though you will lose in-line capitalization on proper nouns and acronyms).

9. Rename all the files in a folder.

What It Does: Renames all of the files in a folder to the same name (adding a number at the end to prevent duplicates).
Level of Evilness: 9 – Unless you immediately do Ctrl+Z, there’s no easy way to get the original names back.
How to Do It: Go to a folder with files in it. Hit Ctrl+A to Select All, Hit F2 to Rename the first file, Enter the name you want to give to all files, Hit Enter.
How to Fix It: Ctrl+Z can be used until another folder action takes place (such as deleting a file).

10. Cause a Blue Screen of Death on Command.

What It Does: Triggers a BSOD (Blue Screen of Death) any time a specific shortcut is entered.
Level of Evilness: 10 – This takes a bit of pre-work on the computer, but you could conceivably cause a BSOD on a friend’s computer in seconds after it’s been setup.
How to Do It: Enable debugging mode (follow this guide), restart the computer, then hit Ctrl+Scroll Lock (twice) to cause the BSOD.
How to Fix It: Disable debugging mode.

Have any computer shortcuts you use for pranking your co-workers? Share them in the comments? Want to prevent your computer for getting messed with, remember the most important shortcut of all: WindowsKey + L to lock your computer.