Hi bestrada11, You may be static shocking the floppy as you go from computer to your control. I have noticed that I have had that problem this year and have had to reformat the disk on the control in dos then try to run scan disk from the dos prompt in my win xp desktop where I do my custom threading routines for my T400 lathe control. If it reads the disk on the desktop It will usually work ok. But as I say I have ruined 6 floppy disks this year alone from static electricity. My T400 control does not crash when I get the dos read error, but my partner 1 does and I have to reboot the control and then I get a new disk and format it on the Centurion 5 control and it will read ok when I copy a file from my desktop.