How about change another ethernet port of TD-W8960N to connect to your main router? Or if you connect to the modem via a cable, can you get internet? the settings are correct.

How you test the speed? wired or wireless connection? is there any comparison speed test result?

Have you tried restarting your main router? Double check whether you put the correct security type of the main wifi.

Is your router network working properly?If you connect your pc to the same ethernet port which is connecting with NC450, does it work?It seems we need to check the router' s network firstly. Then, we...

If we want to set it work at access point mode, the configuration method is the same. Can you get two pcs work if you connect them to TIM at the same time? If no, we can't use both 841 and 9970 like...

Is there any high power appliance near the powerline units? Have you tried changing the place where you plug? According to your description, it seems there is some high network or electrical...