For Squad we had the same issue, but were able to play shortly after an Update. Fortunately someone had some .eac files in his prefix, which with some tweaks to the user.reg, led to us to be able to play again.
If someone on here is able to get those files Post Scriptum can be run on linux
Solution for Squad: https://github.com/ValveSoftware/Proton/issues/938#issuecomment-656974087
PS: I've tried to use the .eac files from the Squad Fix. This removed the IGClient Error, but after joining a server got the message "Anti-Cheat Bad Authentication". So it seems that to fix this issue only some valid .eac files are needed.
Can we get info out of the .eac file as it would appear on windows? I am not sure that anyone would have the .eac files in a wine prefix. I might be wrong, but I do not think post scriptum ever had linux support.
Does anybody know anything one way or the other about what @Frick-David asked?
I'm currently installing Post Scriptum on Linux. I also can boot into Windows 10 on the same PC, where I already have Post Scriptum installed. So I can test things and get files if needed.
I have tested compatibility using this guide https://squadfm.org/#installation-linux-only which removed the error.
I then used the .eac files which I got from my windows installation of Post Scriptum, specifically the .eac.metadata file which contained the sha1 and etag codes/keys as I will show you.
sha1=299f2b803fea1d1584689e452c515cb68b8248cb etag="60938db7865e6f8d912db90bae51422a"
What I did was copy these codes from the .eac.metadata file opened in my text editor and paste it in the wine version which I got from the guide. But this did not work. And I guess it's because of the other .eac file not being correct.
So multiplayer still does not work
Same error still persists today... Any progress on this?
@Am0rphous I just found out that this game is actually a mod of "Squad" made by other devs (Periscope Games). The good news is that "Squad" devs (Offworld Industries) is now acquired this game (which has been abandoned for more than half a year), which is promising because last time I played "Squad" it had zero tinkering to get to EAC protected servers.
to continue on from @antimech 's comment, the game has also now been rebranded as Squad 44, so this issue (and other places, like protondb) will have to update accordingly
Compatibility Report
System Information
I confirm:
Symptoms
Error message shows after starting the game:
And of course multiplayer won't work, while the very similar game "Squad" (which I believe from the same devs) works fine without even tinkering (at least for some players).
Reproduction
Just start the game.
steam-736220.log