Ok I've switched the adapter and extender and now I've got the TP Link connection appearing, HOWEVER, it won't connect when I enter the network key.

vieldcs wrote As I know, the powerline wifi extender can work with the old password after upgrading the router. If do need to upgrade the password for the powerline extender, try this utility...

Model : Hardware Version : Firmware Version : ISP : I have the AV500 Powerline Adapter and previously had it working but we've recently had a change of internet (same ISP). Now I need to update the...