as others have advised above, a thumb drive may be prefable if you have usb ports available. But dos may complicate its usage. However floppies are fine if you prefer and PKZIP works fine with them.
I do not understand this:-
the error is after i format and write on the second pc and it messes up the first.
if i write again with new disks it works & corrects the first pc.
[i did not try with old formatted disks- the formatted disks do not show errors]
It suggests you are using the PKZIP quick format command, but surely format and write occurs on the first pc, not the second?
I still think you should try my earlier instructions. A quick format will not cause a problem with them.
Advise the PKZIP/UNZIP parameters if you like.
I suggest you spend more time carefully explaining yourself, as the problem itself and later posts (e.g. #9) are not as comprehensive as they could be. You can use the edit facilty to change them for clarity if required.
I wondered if there is incompatabilty between the ZIP programs. This might occur if you have are using a PKUNZIP that is an earlier version to that of PKZIP.
As a matter of interest, where are you based? I am in Hammersmith, West London.
Good Luck - Keep us posted.