As update: this problem do not appear when using system's Wine.
@juliotux I got Anno 2205 to work with my stock Steam installation and one additional fix.
PYTHONIOENCODING=utf-8 to the games launch optionsU-Play Overlay (U-Play->Settings->General->Enable in-game overlay for supported games)The U-Play Overlay Fix prevents a hard game freeze for me after the ubisoft logo and before the game menu.
After this i was able to auto login into U-play and auto start the game and play for about 6 hours with 60-100 Fps on medium graphics setting.
Hi @quantum-byte
I tried your fixes, but still getting the same error. Error also appear in the new Proton 4.2-1 version.
Hi @juliotux
I was able to reproduce your problem Bad file descriptor if i use the launch options PYTHONIOENCODING=utf-8 PROTON_LOG=1 %command%
If i just use PYTHONIOENCODING=utf-8 PROTON_LOG=1 without %command% at the end everything works.
I guess there are some command line parameters which are unpacked through %command% which cause the issue.
Maybe related to logging through python which could causes those broken file descriptors. Especially if the logging gets initialized before subprocesses get created like uplay + the game. If this is the case its not really a fix (more a workaround) and could be a problem with other games as well.
Hi @quantum-byte
Even with your fix, I could not get Anno 2205 running. It seems to be the same problem, however without %command% Proton do not create any log file. But thanks for the help.
Recently, this fix was broken because apparently proton wasn't passing PYTHONIOENCODING=utf-8 to the program. So, I had to add it manually to regedit using protontricks in:
HKEY_CURRENT_USER\Environment
PYTHONIOENCODING REG_SZ utf-8
I also had to link libgnutls.so.30 to .so.26 and .so.28 to make it compatible with proton requirements.
@juliotux could you please provide more elaborate instruction?
Had this issue as well with Proton/Steam's version. If I run the game in a native Wine prefix everything works out of the box. So this must be something Steam/Proton messes up.
Steps to get the game working:
apt install protontricks on Debian)protontricks -c regedit 375910HKEY_CURRENT_USER\Environment and add a new string entry with the name PYTHONIOENCODING and the value utf-8./usr/local/lib/x86_64-linux-gnu for libgnutls.so.26 and libgnutls.so.28, linking to your current libgnutls.so in /usr/lib/x86_64-linux-gnu: ln -s /usr/lib/x86_64-linux-gnu/libgnutls.so.30 /usr/local/lib/x86_64-linux-gnu/libgnutls.so.26 && ln -s /usr/lib/x86_64-linux-gnu/libgnutls.so.30 /usr/local/lib/x86_64-linux-gnu/libgnutls.so.28Note that you will have to exit the game manually at the end, because the Ubisoft launcher is not exiting when you exit Anno 2205.
Game does not work on steam deck game mode currently. It does however work in desktop mode.
I did the pythonioencoding thing and also disabled the Ubisoft overlay, no luck.
Gets through the launcher, syncs cloud saves etc., then seems to crash
Has anyone been able to launch the game lately? All I have is launch errors. "Failed to setup the swap chain" with dxvk and "Failed to setup the depth/stencil buffer" with wined3d.
Arch Linux, Linux 6.7.5, Mesa 24.0.1, Proton Experimental (8.0)
ryzen 5800x3d, radeon 7800xt
dxvk_steam-375910.log
wined3d_steam-375910.log
Anno 2205 (375910)
Issue transferred from https://github.com/ValveSoftware/Proton/issues/9383.
@j4yn1ck5 posted on 2026-01-09T18:43:14:
Ubisoft Connect launches and syncs with the servers, then attempts to launch Anno 2205. Anno 2205 launches a window of blackout, which then closes itself in short order without any graphics display or audio. No exisiting recommended tinker launch steps resolve the issue.
Install Anno 2205. (on Ubuntu Studio 25.10) Press play.
@j4yn1ck5 I'm checking now and the game is working fine with clean prefixes with proton 9, 10 and experimental. Do you still have the same issue?
This is with rdna4 and mesa 25.3.4 and linux 6.18.6, plasma wayland.
@simifor I cleaned the prefix and tried again, running the latest Experimental. Yes, I have the same issue. It has been a very sticky, tinker-resistant issue on my end.
OS: Ubuntu Studio 25.10
KERNEL: 6.17.0-12-generic
CPU: AMD Ryzen Threadripper 2970WX 24-Core
GPU: AMD Radeon RX 6700 XT (radeonsi, navi22, LLVM 20.1.8, DRM 3.64, 6.17.0-12-generic)
GPU DRIVER: 4.6 Mesa 25.2.3-1ubuntu1
RAM: 48 GB
@j4yn1ck5 by any chance, does it help if you change the game's launch parameter to this? WINE_CPU_TOPOLOGY=8 %command%
@simifor That's one of the options I have already tried. I tried it again just now. I can see with my CPU monitor that the Ubisoft Connect process takes significantly smaller percentage of my CPU (reducing from a ~70% spike to ~10%). But the black screen crash behavior of the Anno 2205 process is unchanged.
@simifor I have tried every possible way that AI will tell me how I can limit cpu cores, except for doing it in UEFI/BIOS. But every time I look at the proton log these notifications are still there:
fixme:ntdll:create_logical_proc_info Improve CPU info reporting: system supports 48 logical cores, but only 32 supported!
warn:seh:dispatch_exception backtrace: --- Exception 0x80000004.
If the number of cores is the issue, then it seems launch options aren't capable of solving the problem. Because in all software masked circumstances, It is apparently using CPUID, to receive the correct core count.
@simifor I have managed to solve my issue. It has something do with memory access in regards to my cpu.
This launch option gets the game up and running for me:
numactl --cpunodebind=0 --membind=0 env %command%
AI summarizes the issues as such:
The Latency Wall: By using numactl --cpunodebind=0 --membind=0, you forced the game to stay on the first silicon die that has direct physical wiring to your RAM [1, 2].
The "Ghost" RAM: Since Nodes 1 and 3 on your 2970WX have 0MB of RAM, any thread that wandered onto those cores was trying to "reach across the chip" to find memory, causing the 0xc0000005 access violation you saw in the logs [3, 4].
Is this non-uniform memory access issue something that can be detected for based on hardware and game engine, and patched before someone has to go looking for tinker solutions? Because this was a marathon of frustration to persist through.
proton experimentalx2 2026-01proton 4.2-1x1 2019-03WINE_CPU_TOPOLOGY=8x1 2026-01PROTON_LOG=1x1 2019-03PROTON_LOG=1`x1 2019-03WINE_CPU_TOPOLOGY=8 %command%x1 2026-01PYTHONIOENCODING=utf-8 PROTON_LOG=1 %command%x1 2019-030xc0000005x1 2026-020x80000004x1 2026-02
Compatibility Report
System Information
I confirm:
Symptoms
Python errors crash the game.
The first error encountered indicate bad encoding in some python file. This problem can be fixed by adding
PYTHONIOENCODING=utf-8to the launch options in Steam, as mentioned here.However, when this problem is solved, another Python error appear in the game log:
Reproduction
Just start the game. Uplay log in, search for updates/sync to cloud. A black screen appear and crashes after some seconds.