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nukarockit

Recruit
2 Badges
Jan 19, 2025
1
0
  • Crusader Kings II
  • Crusader Kings III
I keep getting the "Steam runtime communication error" message on the Paradox Launcher v2. I already tried the steps listed on the official Paradox site to remedy it but it persists. CK3 has been causing me problems for a while now. It works when I run it from the launcher, but if I run it through Steam (which is the only way to play the latest version) it takes forever to launch and almost immediately crashes past the main menu.

I've uninstalled all mods, tried to uninstall and reinstall the launcher several times, restarted my computer, verified all files, and I still can't get it to run how it used to.
Its a shame because I really enjoy the game, but the way things are it is simply impossible to play.
 
Make sure none of these files are set to run as the Windows Admin user:

steam.exe
ck3.exe (in the Steam CK3/binaries folder)
dowser.exe (in the Steam CK3/launcher folder)
C:/users/{username}/AppData/Local/Programs/Paradox Interactive/launcher-v2.2025.1/paradox launcher.exe
C:/users/{username}/AppData/Local/Programs/Paradox Interactive/bootstrapper-v2.exe

Does that help?