Custom authentication error preventing multiplayer access with modified R.E.P.O.

I’m having trouble with multiplayer functionality after installing modifications to my R.E.P.O. setup. The main issue is that I can only play in single player mode now. Whenever I try to create a lobby or connect to existing multiplayer sessions, I get a “custom authentication failed” error message. This problem started right after I applied the modifications. Has anyone encountered this authentication issue before? I’m looking for potential solutions or workarounds that might help restore multiplayer capabilities while keeping the modifications intact. Any suggestions would be greatly appreciated.

Some games let you verify files through the launcher to fix this without losing your saves.

Sounds like the mods are causing issues with the multiplayer. Many games have anti-cheat measures that flag modified files. You might want to back up your modded setup and switch to the original files when you want to play online. Some games allow you to have separate installs for mods and the base game, but it really depends on the title.

Try running the game without mods first to see if multiplayer works, then add mods back one by one.

Yeah those auth errors usually mean the game thinks you’re cheating. Most multiplayer games will block you if they detect modified files, even harmless ones.

I’ve dealt with this before and it’s super annoying. The authentication system is basically flagging your modified files as potential cheats. What worked for me was keeping two separate game folders - one clean for multiplayer and one modded for single player. Takes up more space but it’s the most reliable way to avoid the hassle of constantly verifying files.