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You can also use a utility called cmdow - just google it. It can minimize your batch window, resize it, lock it, etc. It can actually do this for just about any window, but it's really nice for batch files. Be aware though - some antivirus programs will classify this as a spyware type program (I thi...

I have ran into this. You simply need to tell copy to copy the file in "binary" mode. (use /b)

copy a.txt +b.txt +c.txt final.txt /b

The square is the End of File indicator or something similar that gets copied when it uses ASCII mode.