I copied some files from a broken installation of windows small business server 2008 using an Ubuntu boot up disk, to a WD passport 500GB hd, roughly 2 years old and used once a week to watch DVDs on my TV (so not overused). I am trying to copy those files using windows xcopy function and getting the “data Error (cyclic redundancy check)” error. I have done chkdsk /f on both the new C drive and on the WD PP drive and there are no bad sectors. Most of the file on the disk (of which there are 50,000) copy fine, but just 3 very small files will not copy. Anyone has similar problems in the past. I am thinking that maybe it is due to the use of Ubuntu boot up disk (perhaps the files were never copied properly) rather than faulty hard disks.