Disconnect modem from WAN port of C7. Connect PC to LAN port of C7 and check IP address obtained after you reset the router.

If routers disconnect from the network, even if remotely access is enabled, we still cannot access the router remotely, can we?

Only your PC and router(LAN port) are connected by an Ethernet cable? Modem is disconnected and Wi-Fi is disconencted?

:confused:Confused... The Wireless MAC Address Filtering feature allows you to control the wireless stations accessing the AP, which depend on the station's MAC addresses. But you want to bind MAC...

As to DDNS capability, TP-LINK do have a plan to make its own DDNS server as I know...But not sure when it will come out... Some of TP-LINK routers can work as VPN servers while WDR3600 or such kind...

25 wireless devices??? C9 may not be able to handle so many of them at the same time... Your previous firmware is older than 150122? As I checked on the website, it is not the latest firmware. Why...