Dell Latitude E6420 does not detect Dell External monitor P221 2H

I have a Dell Latitude E6420 and recently got a Dell Monitor P221 2H.
The issue is that the Laptop is not detecting the external monitor and Monitor is displaying "Entering Power save mode".

I tried connecting it through the VGA cable that came with the monitor and also tried with a DVI-D cable to connect but no success.

I tried going to control panel->Display and tried the option to detect and identify but nothing on the monitor.

The display adapter shows Standard VGA Graphic Adapter if it helps.

What i am missing and how can i get my external monitor working with my laptop.
Any help will be highly appreciated.

EDIT::

–> I tried using both docking station(DVI-D) and connecting directly to laptop(VGA port in this case).

–> Pressing Fn + f8 did not help(nothing happened in this case).

–> I have latest display drivers.

–> Laptop has BIOS version A08 (did not updated this as this is the latest for my laptop)

–> Using Windows 7 64 bit