I am getting a "HDCP" error, but nothing is different from yesterday.

bee23.., I just had a pretty dramatic resolution of this problem that I wanted to share with people. I think knowing the tv and the apple tv makes/versions are very important here. I had an apple tv 2nd generation, os=6.1.? and a 4 to 5 year old samsung fairly high end tv (mite have been a 5500) with 4 hdmi ports. My 2nd gen apple tv worked well with the television for over a year and all of the sudden I started getting the HDCP Playback error on Netflix and even iTunes purchased movies. On another thread markndeb88 suggested that the new "auto" resolution setting on apple tv had upgraded was no longer in sync with most tv's purchased before 2012. The "auto" setting my atv found was 720 60 mghz for some reason. He suggested lowering the mghz to 50 to get it to work. That didn't quite work for me. But on the apple tv I went into Settings -> Audio and Video -> Resolution and the default is to be set to "auto". I tried to set what markndeb88 suggested and the apple tv rejected that and said the tv was not compatible to that setting. But the key here is to try different explicit settings until one is accepted by the apple tv and it will tell you quickly if the setting is incorrect, or that it's willing to use that setting. In my case the apple tv accepted 1280 by 764 60mghz. I rebooted the apple tv, checked to make sure my resolution setting survived the reboot, and then checked the netflix movie that was failing for me. The results were dramatic. The netflix movie worked the first time and it must have failed 15 times when I was playing with it last night. I was using an apple tv hdmi cable for all of this and a kinivo hdmi splitter just to add complexity. I personally feel that all the hdmi cable discussion you see on these threads are a red herring, even though some people report that different cables work for them. I do think this is an apple bug. My 2nd gen apple tv worked for a long time without this problem. Some upgrade changed the auto setting such that it doesn't work for a lot of people. I have never seen anything like this on my Roku's or Chromecast so someone knows how to dynamically adjust to the tv resolution they're talking to without a big problem. The formal Apple answer to this problem that I can see is something about a "Sleep Now" setting Apple TV (2nd and 3rd generation): About Apple TV and HDCP. I think that's bunk and don't waste your time. I noticed this problem is intermittent. One of my iTunes HD movies didn't work for a few tries and then it suddenly played. The Sleep Now solution may tweak the intermittent nature in your favor occasionally. My solution is not to allow "Auto" to find the HD Setting (1280, 720) and to explicitly set your HD resolution for the television that is connected to your Apple TV. I think my/markndeb88's solution to this problem gets to root cause, at least until the next Apple TV OS upgrade.

Power cycle the ATV and TV.

Disconnect and reconnect the HDMI cable.

Here is Apple's recommendations: http://support.apple.com/kb/HT4428