Warhammer 40,000: Dawn of War - Definitive Edition

protonopen appid 3556750Game compatibility - Unofficial

ValveSoftware/Proton#8983 · opened 2025-08-19 by rbjorklin · updated 2025-12-30 · 2 comments · github · game page · search this game

Rrbjorklin 2025-08-19 github

Compatibility Report

Name of the game with compatibility issues: Dawn of War - Definitive Edition
Steam AppID of the game: 3556750

System Information

GPU: AMD RX 6950XT
Video driver version: 25.1.7
Kernel version: 6.15.9
Link to full system information report as Gist: https://gist.github.com/rbjorklin/1e7b0aa236d8913d8276384f8841e84a
Proton version: 10.0-experimental

I confirm:

[x] that I haven't found an existing compatibility report for this game.
[x] that I have checked whether there are updates for my system available.

Symptoms

"Sync-error detected" while playing online multiplayer game. The same issue as reported in the original in #3481

Reproduction

Play an on online game for about 15-30 minutes.

Workaround

It seems to be possible to workaround/fix this by running:
protontricks 3556750 ucrtbase2019

maybe this could be added to the games packaging to fix this for all players out-of-the-box?

Rrbjorklin 2025-08-20 github

Don't know if this is related to the linked PR but Relic put out a hotfix today where they claim to have fixed the issue.

Fixed a desync that led to a crash in Multiplayer games where players on Windows & Linux (SteamDeck / Proton) were playing together.

RRhiyo 2025-12-30 github

UI elements in Dark Crusade and Soulstorm seem to be broken making the game very difficult to play. I've seen this posted a lot on ProtonDB as well - people seem to think it's more specific to Arch/CachyOS/Manjaro

Updating to a newer proton, deleting the games' prefix and rerunning it seemed to have fixed the above issue.

Nothing extracted yet.