We have had precisely the same problems-- need to login every time we run the Netflix application, and get the Netflix can't play this title at this time message. We've been bounced from Samsung to Netflix and back-- each entity blaming the other. All we were told was that the Netflix application is designed to work with a particular Samsung software version. (We are currently running 1029 and Netflix mentioned said we needed 1055 which is not even available for our UN40ES6100 TV). If anyone gets better information, please share!
