I have purchased an HP Pavilion 15-n011tu laptop recently with the operating system Ubuntu 12.04. The laptop is completely fine when I purchase,but after I upgraded to Ubuntu 14.04 version, only WIFI has stoped working. Even we can switch on or off the WIFI. This is a very common problem for all those who purchase HP laptop with Ubuntu OS, since HP is not supporting drivers for any Linux destro.

Solution 1: Solution for this problem is we can purchase Windows 7 or 8, since HP is providing driver support for Windows 8 (both 32 & 64 bit) and Windows 7(only 64 bit). Currently HP Windows drivers are available at the following URL address
http://h10025.www1.hp.com/ewfrf/wc/softwareCategory?cc=us&lc=en&product=5440120

Solution 2: But purchasing Windows OS is costly. Now a days, It is trend to migrating Windows to Linux for developers. In that case, Without WIFI or Internet any laptop is almost waste.

Please follow the following steps for Ubuntu Operating System.

Step 1:Open the terminal and type "lspci" you can find list PCI buses and devices connected to the system.

Step 2: Note your laptop WIFI model, My laptop WIFI Model is MEDIATEK Corp. MT7630e. 

Step 3: If your laptop WIFI model is same as mine (MEDIATEK Corp. MT7630e), download the driver by Clicking Here. Once downloaded the driver, extract and copy files to /etc/ directory as /etc/MT7630E
[NOTE: if your WIFI model is different, you need to search for your WIFI model from Internet]

Step 4: Create Wifi.sh file under your home directory, then copy paste the following lines and save the file.
cp /etc/MT7630E/firmware/Wi-FI/MT7650E234.bin /lib/firmware
cd /etc/MT7630E/rt2x00
make clean
make
bash load.sh
exit
Step 5: For every restart of the laptop execute the Wifi.sh file as root
sudo ./Wifi.sh

Now WIFI will start working on your Ubuntu Operating System also. Thank You :-)