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How can I rejoin two files into one?

Question: 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.

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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.

Do this

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5 comments on “How can I rejoin two files into one?”

  1. Greatings.
    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).

  2. 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

  3. 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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