Read this if you are using visibroker, but it might givestill give you some idea on what need to be done to avoid this error.
There can be communications problem involving VisiBroker Smart Agents.
An existing connection may have closed due to failure at the other end of the connection. A new connection request may have failed due to resource limits on the client or server machine.
When COMM_FAILURES occur due to system exceptions, the system error number is set in the minor code of the COMM_FAILURE. Check the minor code against the system-specific error numbers (for example in the include/sys/errno.h or msdev\include\winerror.h files).
Recommended Action: Use the same port number for all VisiBroker Smart Agents and retry. Consult your VisiBroker documentation.