Unable to use F2 Key without pressing Fn key in laptop

This is not an issue, the reason is that your new laptop has been set up with the fn key enabled.
This means that the controls for brightness, rewind, play, pause, stop, volume, mute, etc do not require you to press the fn key.This feature helps the people who play on their computers or watch DVDs a lot. 

 To Disable this You have to do the following on your Laptops

 HP laptops

•  Press the power button to turn your computer on
• Press F10 key to enter BIOS setup screen
• Use the left right arrow keys to navigate to “System Configuration” 
• Use the up down arrow keys to navigate to the “action keys Mode”
•  Press “Enter” to open the Enabled / Disabled menu
•  Use up down arrow keys to select “Disable” 
•  Press the F10 key
• Use arrow keys to select “Yes” 
•  Press “Enter” to save changes and start windows

Dell Laptops

Hold down F2 at boot up and then go to function keyboard setup and select function behavior instead of the default multimedia behavior.

How to Reinstall and Reset TCP/IP (Internet Protocol) through command line

1.Click on Start button.
2.Type Cmd in the Start Search text box.
3.Press Ctrl-Shift-Enter keyboard shortcut to run Command Prompt as Administrator. Allow elevation request.
4.Type netsh int ip reset in the Command Prompt shell, and then press the Enter key.
5.Restart the computer.

How to determine current domain controller in Client Machine / Server Machine ?

Go To Command Prompt and type

SET L  which will show the logged on user is authenticated  to which DC

to know which DC the computer is authenticated to Type 

nltest /SC_QUERY:YOURDOMAIN.COM

find out to which Site a computer currently belongs
  nltest /dsgetsite