WiFi adapter not found in Ubuntu 18.04

Question

I have recently installed Ubuntu 18.04 in my hp 15bs 145tu laptop. All packages of Ubuntu seem to be working properly but the WiFi adapter is not found, and I can't connect to the wireless network.

How can I debug/fix this?

Answer 1

First, try to connect with the wired Internet connection (or you can use Mobile Tethering) and use the following commands to install missing Wi-Fi drivers.

Clone the repository (use your Terminal):

git clone https://github.com/lwfinger/rtlwifi_new.git

Enter the cloned folder:

cd rtlwifi_new

Check out the extended branch:

git checkout extended

Start installation:

sudo make install
sudo modprobe -r rtl8723de
sudo modprobe rtl8723de

That's it! You have now successfully installed the RTL8723de Wi-Fi driver on your Ubuntu 18.04 system. This repo also contains the driver for RTL8723be and much more RealTek devices.

If that doesn't work just go and do this:

sudo apt purge bcmwl-kernel-source
sudo sed -i '/blacklist bcma/ d' /etc/modprobe.d/blacklist.conf
sudo sed -i '/blacklist brcmsmac/ d' /etc/modprobe.d/blacklist.conf

Reboot. If wifi does not come on, do:

sudo modprobe -v brcmsmac
sudo modprobe -v bcma