Ran into this problem recently and a friend has already determined a workaround. If you stream Netflix through Windows Media Center and are having a problem, here is the fix, I will post it as he sent to me:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">...it might depend on which version of IE (I'm running 9) and Silverlight you are running. But Netflix, Microsoft and Firefox have decided to not play nicely. It looks to be some issue with the Netflix SSL cert but they are all pointing fingers at each other. When I tried to launch a Netflix movie in WMC I would get and error about the page being canceled.
Rather than waiting on MS or Netflix or Firefox to fix the problem which would probably be never, here's a fix
1. Make sure you're not running IE in private mode for this fix.
2. Close both Media Center and IE
3. Open IE and open the Security tab in Internet Options.
4. Disable "Protected Mode" under Internet, it will complain like hell, tell it to STFU! (you can re-enable it after the work around)
5. If you have Netflix.com in your trusted sites, remove it
6. Clear all cache/temporary files (Internet Options/General/Browsing History/Delete..., everything checked EXCEPT "Preserve Favorites website data")
7. Log into Netflix in IE (play a couple seconds of a movie (to double check that it works). Don't exit IE yet.
8. Open Media Center Netflix (while IE is still open)
9. Stream movies again (you can re-enable protected mode and close IE). The work around should stay after that.
Streaming still doesn't work in Firefox, I get a silverlight error and "fixing it" the way Netflix says to fix it, doesn't work. It's probably a security issue because I have Firefox locked down. I don't really care about Firefox because I never watch Netflix in Firefox.
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<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">...it might depend on which version of IE (I'm running 9) and Silverlight you are running. But Netflix, Microsoft and Firefox have decided to not play nicely. It looks to be some issue with the Netflix SSL cert but they are all pointing fingers at each other. When I tried to launch a Netflix movie in WMC I would get and error about the page being canceled.
Rather than waiting on MS or Netflix or Firefox to fix the problem which would probably be never, here's a fix
1. Make sure you're not running IE in private mode for this fix.
2. Close both Media Center and IE
3. Open IE and open the Security tab in Internet Options.
4. Disable "Protected Mode" under Internet, it will complain like hell, tell it to STFU! (you can re-enable it after the work around)
5. If you have Netflix.com in your trusted sites, remove it
6. Clear all cache/temporary files (Internet Options/General/Browsing History/Delete..., everything checked EXCEPT "Preserve Favorites website data")
7. Log into Netflix in IE (play a couple seconds of a movie (to double check that it works). Don't exit IE yet.
8. Open Media Center Netflix (while IE is still open)
9. Stream movies again (you can re-enable protected mode and close IE). The work around should stay after that.
Streaming still doesn't work in Firefox, I get a silverlight error and "fixing it" the way Netflix says to fix it, doesn't work. It's probably a security issue because I have Firefox locked down. I don't really care about Firefox because I never watch Netflix in Firefox.
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