appear events problem in fireworks 1.7

[khorasani]

hi everybody,
I have 7 EST3 panels that are networked together , Port 2 in one of them (panel no.1) is configured Gateway-iii with text , 19200 baud rate and this panel connected to a PC via USB to serial cable that I have installed Fireworks 1.7 on it ; Also com1 is configured as Gateway-iii , boud rate 19200 in fireworks.
The communication between Fireworks system and panels is Ok ,but i have auxiliary port2 fault and when I create a fault or an alarm in system (for test the fireworks) it is needed to restart fireworks or reconnect usb to serial cable until appear events(the fault or alarm) in fireworks!
I changed USB to serial cable , changed port, com, baud rate ...but the problem was not resolved!
any suggestion please?
regards.
Mehdi.