I’m having the same issue and I can’t seem to figure out a solution. I’m not sure if you’re playing on steam deck but I’m trying to do so and I get the same error. I was told that the steam deck was banned from plutonium usage but I’m not completely sure if that’s true. If you’re not on steam deck, I wonder what the solution for you is and if it will apply to me. Good luck brother.

Kalitos when did this ban happen? Only reason I ask is because there’s people on Reddit forums saying they’re still able to play plutonium t6 on steam deck as recent as April of this year. I just want to know if it’s possible to play my favorite COD on the go or not.

Here's the picture I was initially trying to upload with the error. I'm not sure exactly what's banned due to me not being active on these forums and I could not find any sort of answer through surfing the internet. If anybody knows how to solve this so I can run T6 through steam deck, you're assistance is appreciated.

Hey everyone, I’m new to the forums but I’ve been on PC Plutonium T6 for a while now. I recently got a steam deck and wanted to run T6 through that if possible. I’ve done all the setup for wine, Lutris and have the game on steam, yet I keep getting the same authentication error and I can’t load the game out of the plutonium launcher. Any solutions?