Error copying file or folder

[lmcmains]

I had a computer problem. I had 19,700 kma files in my Hoster songs folder. I couldn't load some of the songs in hoster. So I deleated my songs folder, I had all my files backed up on external hard drive also. Went to copy kma files back to my songs folder in hoster and keep getting an error. Error copying file or folder, cannot copy sc8720-9;data error (cyclic redundancy check).
I try to delete that file and it says it is a bad file and won't delete it. Then I try to recopy and it may be another file that is bad. Anyone ever had this happen. I have Hoster 2.110. Never had this proplem before.