If you are receiving the following error then follow the instructions below to resolve the issue:
"There was an error downloading your purchased music. An unknown error occurred (-50)."
Step 1) If you have any of the following, you will have to configure them to allow certain domains through. * Firewalls * Web Accelerators * Ad Filters * Virus Protection Software
Step 2) Follow the documentation from each of the listed applications to fix the issue. Allow these domains to go through to iTunes: * itunes.apple.com * ax.itunes.apple.com * albert.apple.com * gs.apple.com
If you are receiving this error because of this message: "Error (-50)" when downloading purchased videos, then delete the cached video files of the download, and start the download again from the beginning; this will resolve this issue.