I joined the Arch Wiki because I think that setting up wifi can be explained better than it has been.
I got the following message after rebooting during the installation:
Scanning for networks... You need to install 'wpa_supplicant' failed No networks found
In order to remedy this, you have to install 'wpa_supplicant' before the reboot. This can be done during the 'pacstrap /mnt' step.
In my case, I had followed the wiki blindly, and had set up a dhcp service in the following way:
[root@archiso /]# systemctl enable firstname.lastname@example.org
That creates a conflict with netctl.
After the reboot, wifi-menu would not work. Here's how I fixed it:
# ip link set wlp3s0 down # wifi-menu # wifi-menu -o # cd /etc/netctl # netctl start wlp3s0_TP-Link # netctl enable wlp3s0_TP-Link
'netctl' expects the wireless device to be in a down state. 'wifi-menu' wraps 'netctl'. 'wifi-menu' will not work unless the network device is in a down state.
In the above list of commands, "wlp3s0" is the name of the wireless device in the computer. "TP-Link" is the name of the router. Arch Linux's "wifi-menu -o" command creates a communications profile made of these two elements. That profile resides in the "/etc/netctl/" directory.
This information took me two years to articulate.
The wiki needs to have a better wireless configuration section.