Hey @david64  Thanks for replying. I have managed to resolve the issue.  It appears that something messed up one of the configuration files (com.apple.airport.preferences.plist) in /Library/Preferences/SystemConfiguration. Below are the steps I took ... Took a copy of the backed up version Renamed the current version of com.apple.airport.preferences.plist to com.apple.airport.preferences.plist.new Renamed the backed up version to com.apple.airport.preferences.plist Rebooted the Monterey mac Re-added the VR1600 and Powerline networks The above steps re-established Internet connectivity from both the VR1600 and Powerline networks. Thanks again for your help.  It was deeply appreciated !! ... View more

Hey @david64  Thanks again for replying !! Below are the answers to the questions ... Yes, I can confirm that my old Mac on the Powerline network can ping the Monterey mac on the RE305 network I moved the Monterey mac to the VR1600 network and received a new IP address Using the old Mac (on the Powerline network), I successfully pinged the Monterey mac on the VR1600 network I have checked the settings on the old Mac with the Monterey Mac and they are the same Here's what I have tried so far on the Monterey Mac (without success) Rebooting (several times already), plus shutting down overnight Removing the Wifi configuration and then re-applying the Wifi configuration Removing the Wifi configuration, rebooting and then re-applying the Wifi configuration Some more information ... I moved the Monterey mac back to the RE305 network and can successfully ping the TPG gateway (10.x.x.x) as well external sites (eg, www.theage.com.au) When I move the Monterey mac to the VR1600 or Powerline networks, pings to the TPG gateway time out as well as pings to external sites (ie, www.theage.com.au) In the last couple of days I bought a USB-C/Ethernet adaptor for the Monterey mac When I plug-in the Monterey mac to the Powerline and VR1600 networks via cable/Ethernet, I can ping the TPG gateway and external sites A really baffling issue ... Thanks again. ... View more

Hey @david64  Thanks for your speedy reply !! Please find below answers to the questions ... My mac only has wifi Model name for the AV500 extender is TL-WPA4227 KIT(AU) Ver: 1.0 Model name for the AV1200 extender is RE305(AU) Ver: 1.0 The VR1600 is running in normal mode with the Internet light on I have rebooted the VR1600 once already.  My other devices (eg, Ipad, mobile phone, other Windows laptops) can connect the Internet with no issue. My older Mac can connect to AV500 with no internet issues A very curious situation.  Not sure if the AV500 or VR1600 needs patching. Thanks again for your response !! ... View more