Sometimes you can see error ERROR NETWORK CHANGE usually in Chrome. You can fix this by disabling ipv6.

Open /etc/sysctl.conf and add following at the end of the file: 

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1



Then run

cat /proc/sys/net/ipv6/conf/all/disable_ipv6

and you should get 1.