Error: "Could not open a TCP/IP socket. Address already in use. The combination of IP address and receive port is in use by another program. Please edit the communication profile, click advanced and change either."
This error message indicates that another program is trying to use the same port number. This normally occurs when a computer is trying to run the Guest and Host at the same time. In the default communication configuration they both are trying to use port 6502. In most cases it is not necessary to run both simultaneously. One module should be closed before launching the other.
There are two settings in the NETOP.ini file (located in C:\Windows) that address this behavior. Open this file in Notepad and look for the heading [COEXISTENCE]. Under that heading there may be the following variables:
If these values don't exist, they can be added and/or modified.
Coexist=1 enables the auto unload and reload of the Host when launching the Guest.
Coexist=2 enable the Guest and Host to run simultaneously.
Load_Warning=1 will alert you when you launch a Guest that a Host currently running and it will be stopped while the Guest is running.
Load_Warning=0 will disable the warning that the Host is unloading so that the Guest can run.
If you need to run both the Guest and Host at the same time and want to use the communication profile "TCP/IP" with both modules you can do that by modifying the TCP/IP receive port in the Guest: