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🛜Connection

How to Fix Space Marine 2 Mods Detected Error

If Space Marine 2 blocks you from multiplayer with a "Mods Detected" error, it usually has nothing to do with mods. The check runs over the network, and when it cannot complete — because of a service outage, security software, or your provider's routing — it fails closed and reports modified files that are not there. Players who have never installed a mod see this error regularly.

If you have not tried the checks on the main connection page yet, start there: → How to Fix Space Marine 2 Connection Issues

Symptoms

  • "Mods Detected" blocks online co-op and you use no mods

  • The error appeared after a game update rather than after installing anything

  • The campaign works and only online modes are blocked

  • The error comes and goes on different days with no change on your end

  1. Add the game folder to your antivirus and firewall exceptions. Security software blocking the check is the most common cause we see. Add both the installation folder and the game's executable to your exception list, in Windows Defender and in any third-party antivirus you run. In Windows Security: Virus & threat protection → Manage settings → Add or remove exclusions → Add an exclusion → Folder, then select your Space Marine 2 installation folder.

  2. Change your DNS. If the check cannot resolve our verification servers, it fails. Use Cloudflare or Google instead of your provider's DNS. Open Windows Settings → Network & Internet → your connection → Edit next to DNS server assignment → switch to Manual → turn on IPv4. Set the preferred DNS to 1.1.1.1 and the alternate to 1.0.0.1 for Cloudflare, or 8.8.8.8 and 8.8.4.4 for Google. Save, then restart the game.

  3. Verify your game files. An interrupted update leaves altered files behind and can produce the same error for legitimate reasons. Verify to rule it out.

    • Steam: right-click Space Marine 2 → Properties → Installed Files → Verify integrity of game files.

    • Epic Games Store: library → the three dots under the game → Manage → Verify.

    • Microsoft Store: Settings → Apps → Space Marine 2 → Advanced options → Repair. If you have installed mods at any point, delete anything you added by hand in the installation folder before verifying — a mod manager does not always remove every file it wrote.

Still blocked?

Send us a report including your platform, region, and internet provider. If the error comes and goes rather than blocking you constantly, say so — that pattern points at a service problem on our side, and we treat it differently.

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