There is a long discussion here:-
Those who have upgraded from Silverlight 3 to 4 all seem to are getting Netflix Error Code: N8156-6013.Strangely reverting back to Silverlight 3 is fixing the problem.In one sight I read that deleting the “Playready” folder solved the issue (as described here:-http://angrydome.org/post/621143108/netflix-error-code-n8156-6013 ).But actually it’s not that simple.There is an interesting discussion here too:-
The question is -is it a Netflix issue,or is it a Silverlight issue?
A user (a1smith) in greenbutton’s discussion thread commented:-
It looks like Microsoft’s Tuesday updates solved the problem. I saw 7 updates pending. I had regressed to Silverlight 3 so I added the Silverlight 4 update back to the update list and did all of the updates. Now, Netflix is working in IE8 and in WMC in Win7 x64. When I tried WMC I had to reinstall Netflix and I had to reenter ID and PW and then it authenticated one more time (on its own) but then everything worked fine.
On my XP PC Netflix works fine in IE8, don’t have WMC in XP so can’t comment.
It seems like the Silverlight 4 update should have been in this Tuesday batch instead of on June 4.
Update – well, the updates got Silverlight 4 working but the Netflix GUI is slow (moviebox icons take a while to load, some just show broken file icon) and I’ve had one WMC restart while in Netflix. Mouse click response is sluggish (~ 5 seconds to respond). So, better in the sense that Silverlight 4 works now but not completely fixed . . . . but response is better than what some people are describing.