Why user can not access phones'web with LCD displaying 192.168.1.XXX?

FAQ ID:12591
User may meet the following situation: connect the phone's WAN port to the local area network in the office, and start the phone, phone gets an IP address like 192.168.1.XXX from the network, however, user can not access the phone using this IP and the same with ping in the command window of the PC.
What to do?
Actually, this is because the default IP address of phone's LAN port is,  when the WAN port gets an IP like 192.168.1.XXX, both the two ports of the phone work in the same IP segment, this will make user can not access the webpage.
The solution is: 1)  Disconnect the WAN port from the network;
2) Connect phone's LAN port to the PC directly;
3) Login phone's web using and go to Network-->LAN page, change the IP address of LAN port to be or any others except 192.168.1.XXX; 
4)  Connect the WAN port to your local area network, then user can login phone's webpage using the IP phone gets.