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You Never do it....!!!!!!!!!!!!

Suresh Prasad (www.aubsp.com) (15630 Points)

23 March 2011

Nobody can create a FOLDER/file anywhere on the computer which can be named as “CON”.

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7 Replies

Sagar (student) (326 Points)
Replied 23 March 2011

its a very old trick

1 Like

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Suresh Prasad (www.aubsp.com) (15630 Points)
Replied 23 March 2011

Originally posted by : Sagar
	its a very old trick

Wowwwwww..............you know it.....!!!!!!!!!!!

Did you know the reason ????????????

harpreet singh (Revenue Accountant at PSPCL) (593 Points)
Replied 23 March 2011

Can you create a folder named “con”, “prn”, “nul” “com1″ “com2″ “lpt1″ etc. in windows ?

The answer is NO and YES!

NO because when create a new folder and try to rename it to any one of the above specified names, you know what happens! In Windows XP the folder name automatically changes back to “New Folder” no matter you try any number of times. Where as in Windows Vista/7 when you try to rename the file you get an error message “The specified device name is invalid”.

What is the reason for this? Simple, these names represent the internal devices and hence we cannot create folders with the above names.

YES because it is still possible to create these folders using the command prompt.

2 Like

Lekshmi (Chartered Accountant) (1285 Points)
Replied 23 March 2011

Hey Suresh,

That was in fact news to me friend!!!

I tried, failed.

I googled to find the answer and this is what i found from a site!!!

It is in fact perfectly true that you cannot create a folder named "CON", nor can you rename an existing folder to "CON". However, there is no mystery surrounding this restriction whatsoever. The "team" at Microsoft, and a great many others besides, know perfectly well why you cannot name a folder "CON". "CON" and a number of other character strings are in fact reserved names that go back to the days of DOS and cannot be used to name folders or files. Other reserved names are:

PRN
AUX
NUL
LPT1
COM1
Potential drive letter - A: to Z:
A number of others

If you try to name a folder using one of these reserved names, the name will automatically revert to the default, generally "New Folder". Moreover, if you try to use a reserved name to name a file such as a Notepad or Microsoft Word document you will generally receive an error message similar to the following:

Depending on exactly how you save the file, you may instead receive a warning message advising that a file with that name already exists. However, even if you choose "Yes" to overwrite the existing file, you will still not be allowed to save the file.

It should be noted that, by entering the right sequence of commands via the command prompt, it is usually possible to circumvent the restriction in Winodows and create a folder using a reserved name. However, this may cause other problems and is not advisable, especially for more inexperienced users.

While there is no mystery about this issue, it might have saved user confusion if Windows displayed an explanatory error message when attempting to create a folder with a reserved name as well.

For more detailed information see:
MS-DOS Device Driver Names Cannot be Used as File Names