Multiplayer game using two different projects

Hi, I have created two projects where each scene has a player as implemented in the Multiplayer Network Tutorial https://unity3d.com/learn/tutorials/s/multiplayer-networking using a Network Manager. When I build and run a single project and simultaneously run that same project in the editor, then things work fine as in the tutorial. However, when I build and run each project separately, or run the editor of each project separately, then I get the error message “Failed to spawn server object, did you forget to add it to the NetworkManager? assetId=10a722dbb60160542b789e20d437496e netId=2
UnityEngine.Networking.NetworkIdentity:UNetStaticUpdate()” in the client side. Any idea why this is the case?

Interestingly, when I use the NetworkClient and NetworkServer implementation in the same case, I manage to exchange messages between the client and the server on the different projects. Its just this case with the network manager that doesnt seem to work.

Both projects are running on the same machine under localhost.

Just to update this. Found that MLAPI (GitHub - TwoTenPvP/MLAPI: A game networking framework built for the Unity Engine to abstract game networking concepts.) solves this issue.