Dealing with an exception: “An attempt was made to access a socket in a way forbidden by its access permissions”

I was attempting to bind a remoting listening to a particular port and kept receiving an exception when attempting to bind on the production Windows 2008 R2 server itself – it always worked fine on both my development box and our test server. Here’s the exception:

Exception message: An attempt was made to access a socket in a way forbidden by its access permissions
Stack Trace:
   at System.Net.Sockets.Socket.DoBind(EndPoint endPointSnapshot, SocketAddress socketAddress)
   at System.Net.Sockets.Socket.Bind(EndPoint localEP)
   at System.Net.Sockets.TcpListener.Start(Int32 backlog)
   at System.Runtime.Remoting.Channels.ExclusiveTcpListener.Start(Boolean exclusiveAddressUse)
   at System.Runtime.Remoting.Channels.Tcp.TcpServerChannel.StartListening(Object data)
   at System.Runtime.Remoting.Channels.Tcp.TcpServerChannel..ctor(IDictionary properties, IServerChannelSinkProvider sinkProvider, IAuthorizeRemotingConnection authorizeCallback)

Though Googling gave some suggestions to run the process as an administrator (no effect), the actual problem was that my process was trying to listen on a port that was already taken by another listener. Since the port was already in use, it couldn’t bind and I received the exception. Stopping the other process resolved the issue immediately.

Not really a clear error message, since it really had nothing to do with permissions at all, but there you go.