Quick Fix
Apparently, Mac OSX Mavericks, El Capitan, and Yosemite can experience IP Address conflicts with other computers on the same home network (particularly with Verizon), causing it to drop its connection with annoying frequency. The error message “network cannot be joined” is virtually useless in figuring out how to fix it, as are nearly all mac user forums.
However, I stumbled across a youtube video with the solution. Alas, the creator didn’t speak, and includes no written instructions, so you have to sit through a very slow demo to see what to do. I thought I’d do everyone a favor and write up the steps.
If you’re having this issue, here’s a quick fix to try:
– Open the wifi menu
– Click “Create new network”
In the dialog that opens:
– Choose a channel other than channel 11
– Click “Create”
The dialog closes, returning you to the wifi menu
– Choose your network from the wifi network list
Repeat the above for each mac on the network, using a different channel number for each.
You should now connect to the network, and the annoying network dropping, with it’s ever-so-helpful “network cannot be joined” message should be a part of your past.
Why a channel other than 11? Channel 11 is the default channel that will be set for any computer joining your network. You probably don’t want a new computer or a guest to bring about the return of the annoying network drop.