Need Help Can Install Apps form my Harddrive Iphone 4 4.2.1

Hi,i have a Iphone 4 Ios 4.2.1 no Simlock, everything is alright but when i try do Install a App over Itunes from my Hdd comes an error Unknown error can Install this App Error 0xe80080001 like this ?? i dont now why ?! but otherwise the apps from Itunes Store i can Install with no probs ! I tried everything Install and re-install Itunes nothing worked ! Pls can anyone help me ?Thx Greatnings Ramco79Message was edited by: Ramco79 Iphone 4 iOS 4 4.2.1