Netflix isn't using Silverlight for Macs at the moment if you're on Safari. It's a new version of HTML5. The irritating thing is that Netflix knows about this issue, and keeps telling people to "just switch over to Chrome," instead of trying to figure out what the actual issue is. I'm having the same issue the OP and other posters are having, in that I have a relatively new MacBook Pro (2011), with no external monitor, no external plug-ins, e.g. nothing fancy, and am getting constant error codes, including this code on a regular basis. And Netflix's response is to switch to another browser instead of fixing the problem.