MS-DOS Install Issue

I used to have MS-DOS on 3 floppy disks. They eventually went bad, so I got a friend of mine to email me the files from each of the disks. I then copied the files to 3 corresponding disks.

My problem is that when I try to boot from the 1st disk and start the DOS install, I get ‘non-systems disk error’.

I don’t have a DOS machine to use the ‘format a: /s’ command to make it bootable, and if I can’t use that command through windows.

I also tried going to www.bootdisk.com and downloading the ‘dos boot disk’, but that doesn’t start the setup, just starts the computer.

I was never a DOS guru. Is there anything else I can do??