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Not only is it possible to rejoin two files into one, you already have the tool on your machine to do so.

I split a file a while ago. I don't have a copy of the program used and I can't remember what it was. All I know is that it split the 2 files into segments ending in ".1" and ".2". Is there a program out there that will universally rejoin files? Or do I have to keep hunting 'til I find the program that I used?

The term for what you're attempting to do is called "concatenation" - basically splicing two files together to create a single file.

And the tool's already on your machine.

The copy command in Windows will do it.

In a command shell:

copy file1 /b + file2 /b file3

Will join file1 and file2 to create file 3. The "/b" indicates that Copy should treat the file as binary rather than text.

Article C2295 - March 1, 2005 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

March 2, 2005 11:32 PM

I would like to suggest an easier way to do the same process.

Do just like this at the directory where pieces are:
copy/b 01.ca1+02.ca2+03.ca3+04.ca4 wimamp.exe
Where: first piece+2nd_3rd+4th and else,equals the final file name splited, which name you are supposed to previously know.

For example I splited Winamp.
System will act then:

D:\Util\Win-util\Splitters\Fsplit>copy/b 01.ca1+02.ca2+03.ca3+04.ca4 wimamp.exe
1 files) copyed(s).

March 22, 2005 8:03 AM

Can u please tell me how can I split the files when I joined files with copy /b


October 27, 2008 3:47 AM

i use file splitter & joiner 3.1 for problems like yours.. its just a small apps.

July 24, 2010 3:37 PM

follow below steps to split files...

1. change extension to .rar of merged file
eg. final.jpg to final.rar

2. now open that .rar file and u can copy
your inner files from there by extracting

Best Luck

August 15, 2012 11:24 PM

I used the command like

copy /b file.jpg+hotfix.rar filehotfix.jpg

Now the command is succ but now if i try to unzip i am not getting the hotfix.rar files what to do some one help me

That's correct - by prepending a .jpg to a .rar file like that you've broken the ability to decode the .rar. To be honest I'm not sure why you joined the two files together like that.

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