hostapd gives error nl80211: Register Action command failed: ret=-19

Question

I'm trying to get hostapd working on a RT3290 (pci-based) network adapter, and a Ubuntu 12.04.3 LTS release. I use the approach taken in How to setup an Access Point mode Wi-Fi Hotspot?

I verified with the "iw list" command that it has AP mode for acting as a access point.

When starting the hostapd daemon, I get the following error:

# sudo hostapd -d /etc/hostapd/hostapd.conf
Configuration file: /etc/hostapd/hostapd.conf
nl80211: Register Action command failed: ret=-19 (No such device)
nl80211: Register Action match - hexdump(len=1): 06
nl80211: Failed to register Action frame processing - ignore for now
nl80211: Add own interface ifindex 0
Could not read interface wlan0  flags: No such device
nl80211 driver initialization failed.
ELOOP: remaining socket: sock=4 eloop_data=0x8a5b900 user_data=0x8a5bea0 handler=0x807c5e0
ELOOP: remaining socket: sock=6 eloop_data=0x8a5dd30 user_data=(nil) handler=0x8086770

What can be wrong with this set-up?

Answer 1

Removing a space character after the "interface=wlan0 " line solved the issue.

I had copied the hostapd.conf from a website: hostapd is due to a bad implementation very sensitive to whitespaces.

Answer 2

The answer is here only

  Could not read interface wlan0  flags: No such device
  nl80211 driver initialization failed.

1. you may have disabled your wlan0 , so please enable it , if it is so.

2. The device drivers are not installed properly , reinstall the drivers.

3. If your wireless device has connected with some other name like wlan1 or wlan2 , please edit that file and replace it with the corresponding device name.