Strange problem copying files.....

HI Folks,

Id be real interested on any thoughts on what might be going on here.
This is the situation so far:

1. Backed Up data from computer A to computer B by plugging in the the
hard disk to computer B (via a USB-IDE adapter). Just a bunch of pics
under My Doc's.

2. Formatted Computer A and reloaded Windows XP.

3. Plugged computer A's hard disk back into computer B (via USB-IDE
adapter) and went to copy the files back. Started to copy ok then got
a dialog box from down near the clock (one of those yellow ones) that
says Corrupt File and goes onto say the directory is corrupt and
unreadable (and lists the path to the destination - not the source)

4. So I tried to copy the data on computer B between two hard disks on
computer B, copied no problem, so the problem is deifnitly not with
the source......

5. I ran a surface scan on the hard disk from computer A and its all
ok.

6. Tried copying by plugging the Hard disk from Computer A directly
into the hard disk controller on Computer B - same error.

7. Ran chkdsk on hard disk from computer A - found truck loads of file
system errors which it fixed, but still could not copy.

8. Just to be sure the errors chkdsk found were due to the errors in
the copying operation I formatted the disk again and reloaded windows
- ran chkdsk and it was fine. Tried the copy, got the same errors
copying, tried chkdsk again and it found similar errors to last time.
So this tells me the copying operation is screwing up the file system.

The question is why?

And how to fix it?

Cheers

-Al

And whats even stranger is that if I format the disk, and dont put XP
on it, I can copy the files just fine!