How to play Multiplayer / Spec Ops with your friends without errors

1. Go to Official Hamachi website https://www.vpn.net/
2. Download it
3. Follow the instructions on installer
4. Skip unnecessary options
5. Restart your PC

NOTE: Free version of Hamachi is capable to have maximum amout of 5 people in one LAN network.

1. Run Hamachi
2. Run Hamachi with power button
3. Register or Login to your account
4. There are two ways to do it:
- Create network
Give your network name and password to your friend to join it.
- Join network
Get a network name and password from your friend to join it.
5. You are now in one LAN network!

1. Open MW3
2. Run Hamachi
3. Turn on Hamachi
4. Make sure your network is online (same with your friend)
5. Go to Spec Ops or Multiplayer
6. Invite your friend via Steam or via Friends tab in Call of Duty
7. Done!

Thank you for reading this tutorial!
I hope it helps a lot of people who are struggling with this problem!
If you have any questions writ them in the comments and I can try to help you!