Document become nonsense characters

[Jacky]

Dear all,

I am using Windows XP and Office XP. I have a lots of
document/Powerpoint/Excel storing in my computer. One day I backup my
documents using Move to a network share and after that move back to my
orginial hard disk, I found that some of my documents become nonsense
characters.

I was not enable EFS nor doing any change, however, I found that all the
"date modified" in the files become the new date when I move back to the
folder.

Do you have any insight and do you know how to fix those document, I have a
lots of document and most of them are very important, please help!

Thanks and Regards
Jacky