I've got a home theatre PC that just recently has stopped allowing HDCP content. It has a 280X connected to a Yamaha AV amp on to a Panasonic projector. It runs Windows 10N 64bit. It has worked fine for a year.
It's definitely not a hardware problem; there are several other HDCP-capable systems attached to the amp and they're all working. I've tried swapping out the HDMI cable just in case.
I've also tried uninstalling the driver and going back to an older WHQL version but no joy.
The CyberLink BD Advisor reports it as the 280X driver failing the HDCP test. Personally, I suspect it is a combination of some Windows update and the driver. Anyone got any thoughts as to what to try next?