I keep getting messages from Norton about using their VPN Security on Norton 360, but the problem is, with ExpressVPN the program won’t even run unless I exclude the side from the Norton Norton 360. Once excluded, it works fine.
I would reach out to ExpressVPN and see if they have a solution. I have used both Mullvad and IVPN applications with Norton 360 and no issues. I have also used Wireguard. Are you using the ExpressVPN app or the OpenVPN manual setup?
The problem with my computer is I cannot run a VPN from Norton. My 1 year old router is out of warranty and I have to pay for any changes to ports or whatever they are called. Norton tech support worked on this throwing 3 or 4 techs over several days before admitting failure.
If you are using a Norton 360 product that is a few years old, then your observations are correct. If you have recently purchased a new Norton 360 product, it does come with a VPN feature included in the product.
Norton 360 is not a VPN, as far as I understand, but a protection service for the VPN service one has installed. I'm not sure why you should be speaking of more than one VPN...
Just like with security products, you do not want to run more than one VPN product at a time. They would constantly be conflicting with each other as they fought to control the data being encrypted and then sent out of your computer. This would probably show itself as your computer almost being frozen.