Originally posted by bansheedude17:

We'll give it a shot. I'm assuming dedicated non crossplay server is the pretty standard one right? I don't remember seeing the words dedicated but I'll check tonight. We typically just click start server and don't click cross play since we're all using steam anyway

I just assumed a dedicated server (not the normal game running, just a smaller process without any GUI).
Dunno if it works with only VH clients (with one being the server) and this I cant test.

I tried what I said in my OP by un-/blocking my VH's and dedicated servers internet access (Windows Firewall Control[www.binisoft.org]).
Can't test that with a normal game because I've got only one copy of VH...

https://www.pcgamer.com/valheim-multiplayer-dedicated-server/#section-dedicated-server

Originally posted by M1k3:

https://www.pcgamer.com/valheim-multiplayer-dedicated-server/#section-dedicated-server

Please don't.... any manual advising anyone to install any steam dedicated server via the normal Steam GUI client should be deleted IMHO.
-> https://valheim.fandom.com/wiki/Valheim_Dedicated_Server#Windows
maybe https://www.nexusmods.com/valheim/mods/2365

We'll give it a shot. I'm assuming dedicated non crossplay server is the pretty standard one right? I don't remember seeing the words dedicated but I'll check tonight. We typically just click start server and don't click cross play since we're all using steam anyway

https://steamcommunity.com/app/892970/discussions/0/3123785722651850023/?ctp=2#c3123786900665603249

"Only" the dedicated non-crossplay/-playfab server needs internet to start up. Once it's running you can connect to it even if the internet is no more.
If you find a way to start the server completely offline let us know.

Clients work perfectly fine offline and can connect to LAN servers (VH blocked in FW but not Steam - but I assume it would work with Steam in offline mode too).

Even the goldberg steam emulator[duckduckgo.com] doesn't help (VH server says it's connected but you cant connect anyway - ports are not even open).