Lenovo g5030 not having any hardware switch for wifi or bluetooth after installing ubuntu 14.04
try removing the ideapad_laptop module
for one time test:
sudo rmmod ideapad_laptop
for working after reboot:
echo "blacklist ideapad_laptop" | sudo tee -a /etc/modprobe.d/blacklist-ideapad.conf
I had the same issue, and solved for me. (The solution can also be found here:Wifi Not Working On Ubuntu 14.04 Lenovo G 50-30 )