RS Linx Classics-Enable Gateway option not showing

Hi.

A small problem with my RSLinx Classics.

Some time the ENABLE GATEWAY option with check box disappears and the OPC server is not detected in the OPC test client.
How to get this option back ?

Then when I run RSLinkx as an APPLICATION, i am able to detect and connect to the OPC server.

Please suggest

Configure your rslinx not to run as a service but as an application. Go to launch controlc and uncheck "Always run as a service"