Call of Duty: Black Ops 4 NAT Type error - whats causing - how to fix

I've recently joined the wave of Black Ops, with a new setup and a new mindset I've set out for a mission to play and talk about the newest games over the holidays of Christmas and continuing in the new year.

With Call of Duty still not converting from their peer to peer lobby service, the old NAT type settings still remains an issue all over the world.

I myself ran into the problem after wanting to play the game for the first time yesterday along side some of my friends.

Sad I was to receive the error 'NAT settings is blocking your connection'. Seing the NAT Type set as 'STRICT' within my game came as a shock, as I was sure I had the Port Forwarding 3074 added, as suggested all over the web, as a solution to this problem.
I then began to try and fix this error... Adding all the other port forwarding connections made no difference, even setting up my system as DMZ over the local network didn't fix the problem.

The problem was something else! It took me 30 minutes after this to realize what was going on. As my setup is pretty new, a free trial of Bullguard Anti virus had been activated on the PC.
Now it was an easy fix. For some reason Bullguard have always been the issue for me, which is also why I ditched them earlier.

Disabling the Bullguard independent firewall changed my NAT type to OPEN and I had no problems joining the lobby with my friends!

So, for all of you out there, struggling to join your friends even though every Port forwarding post on Google have been reviewed, try disabling your firewall all together, just for the duration of your gaming session of course.
- No, adding it to your firewalls list of allowed values does not work (at least it didn't for me).

As working with no firewall isn't a solution in the long run, I have set myself the goal to find an antivirus program with a firewall that does not block BO4. If you know one, please list it in the comments and I will update the post for future readers.

Also please let me know if the above solution worked for you. :)