When I launch the game from "C:\ProgramData\FAForever\bin" and try to save skirmish game, I have error "Save Failed". Launching the game from steam (no FAF) allows me to save and load normally.

I do not have Controlled folder access and added folders related to Supreme Commander to Windows Defender exclusions. Still, I cannot save the game.

What I want to do is play campaign and be able to save. I followed this guide https://forum.faforever.com/topic/4702/how-to-play-the-supreme-commander-campaign-offline-and-coop-maps
I can start the missions with no problem, just that no matter what I do the message says "Save Failed" when I try to do so. I have no other ideas how to solve that, I have no external antivirus, just Windows Defender. I do not have this problem with other games.