Concurrent connection to .Net Remoting server


I'm using .Net Remoting to connect between processes. I'm using TCP channel
in a SongleCall mode (on A Win2K machine). I'm calling the .Net Remoting
server from several processes, several threads in each process. From time to
time the following exception is thrown: "No connection could be made because
the target machine actively refused it". Is there a limitation on the number
of concurrent connection can be made to a.Net Remoting server?