I followed this tutorial to setup my Raspberry Pi 3 B+ as a wireless access point. I have gotten to the point where the Pi broadcasts an SSID, but as soon as a client tries to connect to that SSID, my entire Pi crashes and needs to be restarted. The connection always fails once the Pi crashes. I have re-flashed the Pi and started over, copying and pasting as much as possible from the tutorial to ensure I'm doing absolutely everything as instructed. I can't figure out what I'm doing wrong or what's causing the Pi to die every time. Any insight would be greatly appreciated.
Here's the output from running hostapd to the Pi crashing:
$ sudo hostapd /etc/hostapd/hostapd.conf
Configuration file: /etc/hostapd/hostapd.conf
Using interface wlan0 with hwaddr 74:da:38:ef:f2:d6 and ssid "TestServer"
wlan0: interface state UNINITIALIZED->ENABLED
wlan0: AP-ENABLED