Imac will not connect to 5G band but will to 2,4 G wifi
After years of stable wifi connections, my IMac has stopped connecting to the 5GB wifi band but has no trouble connecting to the 2.4 GB band. The 5GB band works fine with all my other stuff (TV, Iphone, Ipad, I Watch).
The hub seems to be working OK and I am beginning to suspect that the issue is IMac related. My Imac is a Mid 2011 model so is still using OSX 10.13.
Am I right? Do I need to install an ethernet link? If so could I use a powerline as the router is downstairs and IMac upstairs.
Any help gratefully received.
iMac 27″, macOS 10.13