Make folders with reserved name such as con

You can't make folders on the desktop that have "System Action" or "Device"  references such

as con, nul and prn. 

Here are others :

CON, PRN, AUX, CLOCK$, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9,
LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9

But... No fear, when Mansehej is here...

Go to command Prompt,

Go to the location where you want to make the folder with name “con”.

write the command:
mkdir \\.\e:\con

To remove the folder again:
rmdir \\.\e:\con

You may also edit the \e:\ to any drive (such as \c:\ ) and may also continue the file path before writing con(or any other reserved names). An example is - mkdir \\.\c:\program files\adobe\nul .