W8901N and your CPE are using the same IP address? Change one of them to be different.

What's the model indeed? Normally if ISP parameters are not built-in in the firmware, it will show no service... You cannot access internet, right? Try to connect its default Wi-Fi name with the...

There are no compatibility issues among TP-LINK powerline adapters except some very old models. Is the PA211 adapter and the PA4010 (or PA4010P) adapter compatible? By extension of question, are all...

whether I can set the DNS config, on the DHCP setting page, to a local DNS server, in ordef to resolve to some devices with crypty names on my network and give them friendly names. Cannot be...

Connect the server to one of LAN ports on WR841N and configure it as an access point. http://www.tp-link.com/en/faq-417.html

All wireless clients cannot open those websites or just the Ubuntu laptop? Did you try to connect directly to your modem to test them? Or can you open them wiring to LAN ports of WR841N? Change MTU...