Hello. My name is***** to JustAnswer. I'm reviewing your question now, and will post back with your reply momentarily.
This could be a few different things: leading causes of that error are:
This alert is often related to a lost connection to the iTunes Store.
If you encounter this alert and you have verified you have a connection to the Internet using Wi-Fi, please review AirPort and Bluetooth: Potential sources of wireless interference.
Can you try to use ethernet cord instead of wifi and see if you get same error?
Then: while on wifi:
If the issue persists, and you're using iTunes for Windows, you may need to flush your DNS and remove pop-up or ad-blockers.
You can use this guide to flush your dns:
Finally, this can occur due to timeouts caused by security software. Check that your antivirus isnt blocking you and that you
correctly changed the username/permissions on your mac.
Let me know what happens. (where are you trying to download movies from and too?)
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