Ethernet not working - self-assigned IP
I've started having issues with the ethernet connection on my 2012 iMac (macOS Catalina, 10.15.7)
I have ethernet wall points and haven't had any issues using them, but the other day I connected to a wall point I hadn't used the Mac on for a while and it wouldn't connect.
Using the same cable in the same ethernet wall point, my smartphone and a streaming box will both connect to the internet. Plug the Mac back in and it says it can't get internet due to a self-assigned IP.
I've tried some of the suggestions online of deleting some files in the system configuration folder, but so far hasn't worked and if anything it may have made it worse as connecting the Mac back in the room I usually use it now has the same self-assigned IP error... My smartphone will still connect in same wall point.
If I reset the router the ethernet will then connect and I can use internet, but if I switch computer off and back on again it stops working and the self-assigned IP error comes back.
Any suggestions?
