[Coco] sdc issue

[Josh Harper]

  hi guys
im having issues
this is my first time using my coco sdc since I got it
what I have done so far
disk controller in slot 4sdc in slot 1slot 1 is selected
typed 
drive 0,off  then emter
drive 0 on real drive is now working
what I am tryimg to do is
backup 0 to 1 then enter it reads the disk like it should but when it should be coping to the sdc all I get is io error
am I doing something wrong
thanks guys for your help