Hey all — For a few months now, I've been unable to connect to my home Wi-Fi network on my late-2012 iMac. It started out of nowhere with Yosemite 10.10.5 — everything had been running smoothly since I updated in late 2014, but suddenly stopped a few months ago. My Wi-Fi network will occasionally show up in the list of networks, but any time I try to join, I get the "cannot be joined" error. Today, I finally upgraded to El Capitan 10.11.3 hoping it would resolve the issue, but to no avail. All other devices in the house (a MacBook Air, a Windows laptop, and three iPhones) can connect without issue. My iPhone and MacBook Air can both connect in the same room as my iMac, and the MacBook is still running 10.10.2. Clearly, this is a problem with my iMac and NOT the router (I even changed service providers last week). I've tried all of the usual suggestions: - Deleting network prefs in Library/Preferences/SystemConfiguration, then rebooting - Renewing DHCP lease - Resetting PRAM - Adding a new network location and using Google DNS - Turning off Firewall - Disabling AWDL - Disabling Bluetooth - Rearranging service order in Network Preferences - Turning off Wi-Fi and Bluetooth on my iPhone 6 (iOS 9.3 beta) I have the following peripherals: USB mouse, Bluetooth keyboard + Magic Trackpad, UAD Apollo Twin Solo, Native Instruments Maschine Mikro, and 2 external HDs. I've had to resort to using my phone's hotspot to get work done, but now, it seems the Wi-Fi Hotspot and the Instant Hotspot no longer work and I have to use Bluetooth. Obviously, this is not viable long term. A clean install would be a last ditch effort. The only Time Machine backup I have is one I made last night before updating to El Capitan. If it comes down to it, I wouldn't be opposed to backing up my /home folder, reverting to Mavericks, and reinstalling everything manually... I'd like to avoid this, of course. Any advice or suggestions welcome. Thanks so much!!