As stated above I can run mw3 smoothly and this problem is with bo2 only
And also my pc also meets the spec and my internet connection is also very fast(600 mbps)

Sorry but can you please speak in english?

Whenever I try to connect to bo2 multiplayer and zombies server the game stops responding on waiting for other players and then after 2-3 minutes it goes back to main screen and says there was an error in connecting to servers.

I am connecting from the servers by pressing f10
I have a fully functional and working network connection
I can connect to servers in mw3 but not in bo2
I can play in offline mode in bo2
Plutonium is allowed in firewall settings