Thanks Kevin Z, Today I tried a solution two AV600 adapters linked with a LAN cable at the main switchboard. One was connected to the house adapter and the the other was connected to the shed adapter...

Quick update:- I've just loaded up the PLC utility program. My adapters within the house are running around about 200Mbs. The shed one is running at 22Mbs to 31Mbs.

Hi Community, I've got two sets of AV600 Powerline Starter Kits (TL-PA411 KIT). They all work fine in my house and have fixed all my WiFi dead zone problems so far. New problem is a steel clad shed...