Webservice with socketconnection

[Hartmut Berger]

A Web service is to make a Socketconnection.
This runs on a Windows IIS 5.0.
The server lies behind a ISA server.
As Applcation is the code ok and has not exception.

The Web service has the following exception:
During a Socketconnection the network was inactive.

What is the cause ?

Here is a sample:

TcpClient tcpclnt;

String antwort;

try
{
tcpclnt = new TcpClient();
tcpclnt.Connect("212.20.8.50", 2500);
tcpclnt.Close();
}
catch (Exception e)
{
antwort = "EXCEPTION = " + e.ToString();

}