Steps to Install Drivers Using PDANet :
1. Download Pdanet from HERE
2. Double click the file you just downloaded.
3. Don't connect your device until that is asked.
4. Continue through the installation by pressing next button, till a screen saying something about drivers appears.
5. Skip to the next step if this one doesn't apply to you. If you already tried installing some drivers, it will ask you if you want to uninstall currently installed drivers and install them using PDANet. Click yes there. Putting clearly, if it asks you to overwrite previous installation of drivers, or anything like that, you have to press yes.
6.The screen that pop-ups next will look almost like the one attached below asking you to select your device manufacturer. Choose your device operator and click ok. If your device is not in the list, click Others and then press OK.
Note: All Indian Device manufacturers like Karbonn, Micromax, Spice, Lava and every other brand not listed in the options that appear fall in the others category.
7. Then a scary warning in red will appear saying that Windows couldn't verify the publisher of the software. Click on "Install this Driver Software anyway". This warning may appear multiple times, keep clicking on install drivers anyway until it stops appearing.
Windows warning during Driver Installation.
8. Then Pdanet will ask you to connect your device to the computer. Now you have to connect your device to your PC/ Laptop using USB cable. Don't enable any modes like: USB storage or tethering. Just let the driver installation complete.
9. Once the installation of the driver completes, you have successfully setup your device drivers.
10. Now exit pdanet from the taskbar by right clicking on the app icon (as shown in the snapshot below). This will prevent pdanet from interfering with ADB/ anything else you are going to use. This is just a precautionary measure.
11. Now you can continue with rooting your device or playing around with ADB and Fastboot.Note :
To check if your device drivers have been installed successfully, try setting up ADB on your PC using this guide. The process will be a lot easier now, as you have already installed the drivers. If on giving the command "adb fastboot", you get a response with your device name (may not be device name laways, in my case it was ?1234567890), your drivers have been installed successfully. Otherwise, if nothing appears under "List of devices attached", then you still have to do it rightly.
Another (easier) method of checking whether your drivers have been installed correctly is, connect your phone to the PC, and don't turn USB Storage/ Tethering on. Start Device Manager, your device should be listed as Android ADB Interface.