Hi Akumtong Jamir,
It appears to be an issue with operating system of your computer. You may back up all the data from computer and may perform an operating system re-installation. For more information on this, you may refer to link: http://dell.to/Qe7jyP
Note: Before you proceed, I will advise you to take a complete backup of your data (pictures, music, applications, videos, documents) as this step leads to complete data loss. Remove all the external peripherals (like printers, scanners, any USB device except keyboard and mouse) connected to your computer.
Once the operating system is installed, you may download and install the drivers for your computer from link: http://dell.to/124xm0d
You may find detailed instruction on installing drivers in correct order from link: http://dell.to/X1IKGu
Once done, try installing Intel My Wifi Dashboard and try configuring the set up as mentioned in previous link.
Please share the findings.
