I've spent a few hours trying to get the secure TCP (based on NegotiateStream) integrated security in .NET 2.0 working. While there is a page on this (Authentication with the TCP Channel), it fails to mention that you need one more property in addition to encrypt, impersonationLevel and authenticationMode. It's called “secure”, and it must be “true”. I didn't see it mentioned anywhere, except when I happened to browse the MSDN Forums: http://forums.microsoft.com/msdn/ShowPost.aspx?PostID=55225

I looked at his config, and realised I didn't have this “secure” property. Problem solved. Also, I recommend checking out http://pluralsight.com/wiki/default.aspx/Keith.GuideBook/HowToAddCIAToDotNETRemoting.html, which has a lot of information about Windows security in general, apart from some specifics of remoting and Kerberos. And, finally, yes, there's one more page where the secure attribute is listed (with some other docs) http://blogs.msdn.com/manishg/archive/2005/04/22/410879.aspx

OK, so perhaps there was some error between the user and the keyboard... but I'm very very excited to see this feature running.