HDCP Error

I think it might be related with Screen Time options, not the HDCP. HDCP is based on HDMI connections.

First thing to know is if you are using your user in login window. If you are using the kids login, it might be related with the content.

Check in System Preferences > Screen Time > Content & Privacy

If you are using your own user, check if you set a screen time limit. If not, check under the Content & Privacy tab to see if something is wrong.

Hi hiphopapotamous,

Let's get some more information to help narrow this down. Boot using safe mode and see if the issue persists on both Macs.

Which app are you using to play the movies you downloaded?

Does this happen to all movies?

Are all of these movies downloaded from the same location?

"If the issue doesn't continue while in safe mode, leave safe mode by restarting your Mac normally. Then test for the issue again. The issue might be resolved.

If the issue returns after leaving safe mode, startup items are probably at fault. Apps can install such items in numerous places, and they aren't always easy to find or recognize. For that reason, you should first make sure that you've installed any available updates for your Apple software and third-party apps.

If updating your software doesn't help, try any of these solutions:

• Test your login items.
• To learn whether software in your user account is causing the issue, set up a new user account, then log in to it and try to reproduce the issue in that account.
• Unplug all accessories from your Mac, including printers, drives, USB hubs, and other nonessential devices. You could have an issue with one or more of those devices or their cables.
• Reinstall macOS.

If you still need help, please contact Apple Support."

How to use safe mode on your Mac - Apple Support

Please don't hesitate to let us know if you need additional assistance.

Cheers.