[QUOTE and were getting a 169.xxx etc IP address][/QUOTE. This address is from operating system not from router. Model of this Homeplugs!?

We want a more info about your network and devices.

You have to install alternative firmware on WR841, then you will see client mode (Gargoyle or DD-WRT). http://wiki.openwrt.org/doc/howto/clientmode http://www.dd-wrt.com/wiki/index.php/Client_Bridge

You have to connect TP-Link by WAN port.

Can you give me some informations about ISP and as you have the internet connected to the router? Can you show me screen shot from TP-Link status tab?

Can you try 30/30/30 hard reset - http://www.jimasek.elektroda.eu/index.php/poradniki/66-hard-reset-30-30-30