Q: how to fix an error -50, how to fix an error -50

err = -50 when downloading from store - https://discussions.apple.com/thread/3697501 - delete incomplete downloads from downloads folder as per http://support.apple.com/kb/TS3297

iTunes Store: "Error (-50)" when downloading purchased content - http://support.apple.com/kb/TS1583

Try going thru preferences, advanced, clear cache.  If that doesn't work make sure youright click I tunes and run as administrator.