I have a multi threaded async System.Net.Socket which listens on a port. I don\'t have any problem if I get a request from HTTP, but recently I had to add https
System.Net.Socket
You should probably use X509Certificate2 instead of X509Certificate. It could be the only step required to resolve this error.
X509Certificate2
X509Certificate
X509Certificate2 has a member for the private key, unlike X509Certificate, and the SSL socket needs the private key to do its job.