Backed up restore problem

HI i have a macbook pro it was not working well so i decided to reinstall the os x. what i did is i copied my user folder which was faisal_sherry and copied everything from there to an external hard drive. I didnt make any time machine backup so now after installing new OS X I named the new user as I had before faisal_sherry and i have updated it. Now Its not allowing me to copy it back. Whenever i try to copy it back it gives some error . Any help because i have all my itunes and iphone backup there which i am more worried about
Regards