First one has to find the IP address of the computer on which all websites are allowed. Just note down the IP address and use enter in your computer and then see if you can access all websites. Also do not forget to create the batch file for this because once the person who had that IP address will switch on his system your IP address will conflict with him and niether you nor he will able to access internet and eventually IT persona will try to find the solution for this so the best way is to find someones computer which stays switched off most of the times.
I have made one batch file for changing the IP address which will help you to change the address in seconds.
Below batch file is for configuring the static IP address whenever is required.
One may change the bold text as per his/her environment.
ECHO 1. Static
ECHO 2. DHCP
set /p choice=Type the Choice:
rem if not '%choice%'=='' set choice=%choice:~0;1% ( don`t use this command, because it takes only first digit in the case you type more digits. After that for example choice 23455666 is choice 2 and you get "bye"
if not '%choice%'=='' ECHO "%choice%" is not valid please try again
if '%choice%'=='1' goto Static
if '%choice%'=='2' goto DHCP
netsh interface ip set address "Local Area Connection" static 10.10.10.2 255.255.255.0 10.10.10.1 1
netsh interface ip set address "Local Area Connection" dhcp