installing rtl8814AU wifi adapter driver on ubuntu 16.04

Solution 1:

This will be easier if you do

sudo apt install git
git clone https://github.com/zebulon2/rtl8814au.git
cd rtl8814au
git checkout 7dde5bd
Then see if make succeeds. If the make command has no errors I would do
make clean
cd ..
sudo apt install dkms
sudo dkms add ./rtl8814au
sudo dkms install rtl8814au/4.3.21

Reboot

There is an issue with the latest commit https://github.com/zebulon2/rtl8814au/commit/3cf715db6f8e021671b72918929a307847e77e92 as the kernel version specified for it should have been 4.17

If you happen to have no internet connection, edit the file usr/local/src/rtl8814au-master/os_dep/linux/ioctl_cfg80211.c at line 350 you will find

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,39))
Change it to
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,17,0))
Then the make command should work without errors