5 Weird Windows Bugs & Easter Eggs You Have To See

WindowsTricks05   5 Weird Windows Bugs & Easter Eggs You Have To SeeWe all know that Windows isn’t perfect. I will take a leap and say that no program is. The thing is, Windows errors, more than anything, can drive people crazy.

But apart from plain old errors, there are also some bugs and Easter Eggs hidden in all versions of Windows. Care to discover 5 of them?

1. Naming & Renaming Folders

For the first one, try to create a folder named CON and you will see the following thing happening:

WindowsTricks02   5 Weird Windows Bugs & Easter Eggs You Have To See

The same thing happens when you try any of the following names:

PRN, LPT1, LPT2, (…), LPT9, NUL, COM1, (…), COM9, and CLOCK$

All of the above names are reserved device names, which cannot be used as file names or folder names, regardless of the file extension. This is a relic from DOS, which has made its way through all versions of Windows, including Windows 7.

Source: Wikipedia

2. Advanced Calculations

Let’s do some basic maths together. Please use your head first. Highlight the next two lines to see the respective answers.

What is the square root of four? It’s two, isn’t it?

And what do you get if you subtract two from two? Zero, right?

Now let’s do the above calculation using the Windows calculator. Type in 4, take the square root and from the result subtract 2. What do you get now?

WindowsTricks011   5 Weird Windows Bugs & Easter Eggs You Have To See

See why they don’t want you to use calculators at school?

To my knowledge, there is no explanation for this result. The operation returns different numbers in different versions of Windows, so it’s possibly a bug by design or an Easter Egg and not some weird functional error. What was your result?

3. Notepad Bug (XP Only)

This bug no longer works in Windows Vista or Windows 7, but if you’re still running Windows XP, give it a try.

Launch Notepad and type the following sentence: Bush hid the facts

Now save the file as anything you like, close it and open it again. What do you see?

WindowsTricks03   5 Weird Windows Bugs & Easter Eggs You Have To See

If you did this in Windows XP, you probably see some weird unicode characters or Chinese characters like in the screenshot above. By the way, I have to admit that I ‘forged’ the screenshot because I no longer run Windows XP.

The explanation for this bug lies in the Windows function ‘IsTextUnicode’. When a text file is encoded in Windows-1252 it is interpreted as UTF-16LE, resulting in the so-called mojibake. It means that Notepad recognizes unicode characters representing Chinese characters and translates them back into Chinese characters.

Source: Wikipedia

4. Microsoft Word Trick

Open Microsoft Word and type the following: =rand (5,10)

WindowsTricks041   5 Weird Windows Bugs & Easter Eggs You Have To See

What happens is that Word creates 5 paragraphs, each containing 10 identical sentences. The sentence will vary, depending on the primary language of your operating system. On English Windows, you will see this sentence: The quick brown fox jumps over the lazy dog.

This is not a bug, it’s a feature! Many of you certainly know that the above sentence contains all letters of the alphabet. In this case it’s nothing more than a dummy or placeholder. Depending on the numbers you pick, you can make it appear in many more paragraphs and copies. The trick is also known as =rand (200,99).

5. Solitaire Bug (XP Only)

Here is another trick that apparently disappeared in Windows 7. Please try it if you have Windows XP.

Open Solitaire and click the following key combination: [ALT] + [SHIFT] + [2]

When you click the above key combination, the game ends right there and you see the cards jumping to the front in waves, as they do when a game is completed successfully.

What did you see when you tried to reproduce the above bugs and what are your favorite Windows Easter Eggs?

Image credits: Antonov Roman

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Elijah Love

Win7 Home Premium 64-Bit: -8.1648465955514287168521180122928e-39

Ray Herring

Win7 Home Premium 64-bit: -1.068281969439142e-19

Probably depends on Locale too, dunno, mine is English Australian

Todd Makeuseof

 The result changes with the view you have set on the calculator.

Adhar Srivastava

 32-bit too


More eggs {xp} can be found here…



More eggs {xp} can be found here…



Whoa, are you still on Word 2003? I know Word 2007 and 2010 does not use that sentence any more.

Sahil Dave

i did on word 2010 and it gave 5 paragraphs about Insert tab !!


Thanks for sharing what it does in Word 2010!


 I got paragraphs about the insert tab and galleries in Word 2007 as well. I think that Word help files are lonely and this is a ruse to try to get someone to read them. I fell asleep after the first 4 words though.


Have to admit that I was on Word 2003 until I updated to Windows 7 recently. Now I don’t use Word anymore and I can tell you that this doesn’t work in LibreOffice. :)


I just did it with Word 2011 for Mac and I got the sentences.


Heh, goes to show that the Mac team at MS Office is still at the pre-2007 stage feature-wise.


that’s it just working


If I recall correctly, the “Bush hid the facts” bug works for any sentence with four words in a four-three-three-five letter scheme.

Adhar Srivastava

 u indeed recall correctly

Saikat Basu

Does anyone know about the ‘Clock’ animation file that can be found under
My ComputerC:WINDOWS. It’s a relic in Windows XP. Not sure if it’s still their in Vista and 7.


I don’t. What is the file called and where is it located in Windows XP? I have Windows 7, curious whether it’s still there.


It used to be “clock.wmv”, I don’t think it’s included any more.


I have C:WindowsCLOCK.AVI on my WinXP desktop. 


Yeah, I remember it as AVI now too. It’s not in the Windows folder in W7 though.

Bruce Epper

The algorithm that MS uses to calculate the square root of a number will almost always result in somewhat inaccurate results (1×10^-19 for 32-bit systems and 8×10^-39 for 64-bit systems). Since Calculator does not display 20 digits, it rounds the result to 2, but it maintains the calculated result for further use. Thus, when you subtract 2 from the result, you are not subtracting it from 2 but from 1.9999999999999999998931718030560858 (approximately) on a 32-bit system.

This rounding error tends to be introduced when attempting to perform binary calculations on decimal numbers. It happens when the number systems don’t have common boundaries (binary & hexadecimal have these common boundaries, but the decimal system does not share common boundaries with either of them).


Thanks a lot for the explanation, Bruce! :) That makes a lot of sense.


but then what about any other calculation with regards to square root of 4? like squrt(4)+1 gives 3 and not any other number. its only squrt(4) -2 which gives wierd numbers. :/


Good point. Maybe they forgot to correct the algorithm mistake in this case. Or it’s intentional, say a reminder to never trust a computer 100%? Could be humor.

Eric Darchis

In this specific case, it’s an issue with the square root algorithm indeed. But usually, this kind of error is due to “floating point” representation. We express a number in 1.234*10^45 while the computer will have 3.46383349*2^79. The computer uses powers of 2 rather than powers of 10. This means that rounds numbers in decimal might not be round in binary. That’s why the approximation errors can sometimes propagate and become visible.

Here, we have 4 which is a round number and its square root is a round number in binary too, so it should work.

I have seen a case where this kind of problem ended up costing thousands of dollars in the company billing system.


I’m not sure if it works on W7 but on XP if you set your screensaver to marque “Who Cares?” and left it a month then it would change to “I do”.


Lol XD


That’s awesome!!!


Wikipedia also has a detailed explanation of the “CON” device bug.

On prior Windows version directly accessing a path like C:concon or C:connul would even crash your system because Windows would ignore the initial path identifier and try to access the device directly.


The notepad bug can still be faked in win7: save it as ANSI, and then in the Open… screen, choose Unicode.


For the calculator trick, it seems to do that with any square root that you subtract the answer from. If you take anything like square root of 25 minus 5, square root of 16 minus 4, etc. it does that weird random answer.

Sahil Dave

i was saving a image of chromes about:about by the name of “Chrome about:about” and it showed me the error that the file cannot be saved by this name…i checked with different options contain : but nothing work… i guess it happens as it’d bug cmd while changing directory and all…


Good thing I mostly use Linux. I only need Windoze for Netflix.

Jack Cola

If you like these Easter Eggs, Google also has a few Easter Eggs to look at too.

Google Translator – http://www.jackcola.org/blog/128-the-best-google-translator-easter-eggs

Google – http://www.jackcola.org/blog/128-the-best-google-translator-easter-eggs


 As for naming & renaming folder, when I type in “con/prn/lpt1/lpt2/com1/com2 & other reserved device name”, what I get is just “New Folder” folder without name. The dialog box does not even appear.


Might be different depending on the Windows version or edition. I took the screenshot in Windows 7 Professional.


Haha that weird result from the calculator doesn’t only happen “virtually”. Some real scientific calculators don’t even know how to subtract specific numbers…

Neat article!


That’s pretty messed up.


type Q33N in notepad and change the font to  size to 72 and font to wingdings
you will see the secret about world trade center attack.


great article!

Tejas Dc

 the calculator bug holds good for sqrt of any number minus the answer..
ex:sqrt16 – 4 , sqrt36 – 6  , sqrt81 – 9 all gives random results..


Thanks for the update, Tejas!