Check system time, reset Internet connection, update root certificates. Updating to the latest version of i Tunes and then restoring should resolve this issue Reportedly happens during failed downgrade attempts (i Phone OS 2.0 to 1.1.1, i OS 5 beta to 4.3.3). Permission error either on your computer or the device. This occurs when the media library on the device is corrupt and cannot be modified or updated.This error is common when downgrading i Phones and 3G i Pads.The i Tunes error 50 is generally faced by the user when the i Tunes is not connected to its database server and the synced apps, music, video and other content are not being shown up on the software interface.The main cause of the error is the Internet Connectivity error.
I have tried quite many "solutions" on the internet for the error 50 while restoring my i Phone 4S, but they don't work. See more questions like this: i Phone 5S comes for activation lock, now error 50 after trying to update with i Tunes?
Keep only the essentials; keyboard, mouse and your i Pad or i Phone.
Your computer displays this error while downloading videos purchased from the i Tunes Store.
If you are on a Windows computer, scan for issues in Windows Registry using the Intel Software Partner, Reginout System Utilities. \Music\i Tunes\i Tunes Media\Downloads\ Delete all contents from "Downloads" folder.
Update i Tunes You might be using an older version of i Tunes.