Hi,

First one red Icon is shows that in your system POS BOX is not connected. If POS BOX is there with system then it will turn into green.

Second green icon is shows that your POS is online (connected) with server. And if it turn into red then your connection with your server is broken and your POS is in offline mode.

I hope it will help you.

 Yes, thank you very much about this. Maybe I don't have POS BOX to connect