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I have created a split file on a Linux system as indicated in this Unix.SE question. However, when I copy that file to a Windows system, I cannot recreate the original file. Using 7-zip gives me an error about it being unable to detect the file as a splitted file, and using copy first-file + second-file output-file gives me a 50kb output instead of the correct 7GB output.

What is the correct way to combine two files on Windows?

share|improve this question… – Lamy Nov 4 '13 at 16:15
up vote 17 down vote accepted

Add the /b parameter to indicate it's binary:

copy /b example1.ext + example2.ext example.ext
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seems to work, though the copy /? documentation seems it might suggest a /B after each file like in bui's answer, but indeed it seems you only need the one /B after copy. As you've done. – barlop May 20 at 8:38

I've used HJSplit in the past with remarkable success. It's pretty straight-forward and simple to use, and it helps avoid typos on the command line (although the command line works just as well)

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