When PosApp (SimGEN / SimREPLAYplus / SimREPLAY) is launched it attempts to check firewall settings that might potentially disrupt the optimal flow of TCP/IP messages between itself and connected devices, e.g. another PC performing remote control and/or the GSS8000 simulator model.
The check is performed because if the firewall is enabled but the user account being used does not have sufficient privileges to allow PosApp to optimise the appropriate firewall setting then the warning message is of significance and hence is displayed as a warning accordingly. The user should take steps to ensure user accounts are configured as per Spirent's PC set-up guides - DCS0036B (WinXP) or DCS0036D (Win7)
However, when the firewall is disabled (regardless of the user account being used) then firewall protocols are not active and TCP/IP comms will operate ‘uniterrupted’, which is what PosApp requires anyway. This actually renders the warning message irrelevant but it is still reported because with the firewall disabled PosApp can’t locate the setting it would otherwise need to check and hence reports that the firewall can’t be configured (even though in this situation it's actually not a problem). Since the message is generic it is displayed as a warning, but can be ignored.