Moon Sweepers Crashing or Freezing? How to Fix It on PC

Update Moon Sweepers before changing renderers or touching your saves. DragDrop Games’ 1.0.5 patch fixes a recurring freeze shortly after loading some worlds, including cases on both DirectX 11 and DirectX 12. Its earlier 1.0.4 update also changed the AMD default and added world backups. Those are better starting points than a pile of launch options.

The world is worth protecting while you work through this. A failed load once looked like corruption for some players even though the save files were intact, according to the developer’s 1.0.3 notes. I wouldn’t discard a Moon you’ve spent hours cleaning just because it stops loading. Start with the documented fixes, preserve the available backups, and keep application freezes separate from a machine that has stopped packing capsules.

Fix the load freeze before experimenting with DirectX

The clearest case is the game becoming Not Responding roughly half a minute after loading a world. Version 1.0.5 specifically addresses that recurring failure in some worlds on both graphics APIs. Install the current update before changing another graphics option to investigate this symptom.

The timing helps identify the developer’s documented case; it isn’t a stopwatch test that diagnoses your PC. Nor does the patch mean every remaining freeze has the same cause. The practical point is narrower: switching from DX11 to DX12, or back again, is not the documented fix for a problem that affected both.

Other launch-week problems received separate fixes. Use the distinctions below to find the relevant change without treating every stopped action as an application hang.

Version 1.0.5 also fixes memory leaks after leaving a world and after removing structures. These are publisher-reported corrections, not a diagnosis of every crash after a long session. If you were troubleshooting on an older build, give the updated game a chance before carrying the same workaround forward.

On Windows with AMD, begin with the developer’s default

Version 1.0.4 made DirectX 11 the Windows/AMD default to prevent AMD GPU crashes. The same note offers -force-d3d12 as a way to opt into DirectX 12. That makes it an override, not a compulsory performance fix.

If you’re on Windows with an AMD GPU and previously added -force-d3d12, open Steam Library > Moon Sweepers > Properties > General > Launch Options and remove only -force-d3d12. Keep any unrelated launch options, then start the game again to try the developer’s default. If you never added that override, leave Launch Options alone.

I’d favor the developer’s crash-oriented default before chasing an API recommendation from another game. This advice doesn’t establish which renderer is faster on your machine, and it doesn’t turn the DX11 default into a universal rule for every GPU. The loading-freeze fix above remains relevant whichever API you use.

Preserve your world before trying a save fix

The useful lesson from the 1.0.3 loading issue is that a world failing to open did not always mean its save was damaged. The developer reported that some heavily cleaned worlds had intact files behind a broken loading process. That historical fix is a good reason to leave the world in place while you investigate; it doesn’t prove every current failure is harmless.

The 1.0.4 notes describe two recovery behaviors. Damaged saves, or damaged parts of them, are restored from backups as the world loads, with a notification. After a crash, the game also checks the save files on its next start and repairs damage. That is the built-in recovery route to try before following an unverified file-renaming recipe.

The documented backup folder is:

C:\Users\[user-name]\AppData\LocalLow\DragDropGames\MoonSweepers\Backups

Replace [user-name] with your Windows account folder. These backups are stored outside Steam Cloud. Before any manual save experiment, keep a separate copy of the available backup directory. Copying it preserves material you may need; it doesn’t repair the crash by itself.

The policy is up to five full world backups per save slot, taken one minute into each session and then every 30 minutes. Don’t read that as five recovery points waiting for you immediately, or a guarantee that you can lose no more than a particular amount of progress. What exists in your folder matters more than what you hope the schedule should have produced.

There is also a version boundary worth keeping beside that advice: the developer explicitly says saves made in 1.0.4 cannot be opened in older versions. Rolling the game back is therefore a poor casual experiment with a world you want to keep. We don’t have a verified manual slot-to-file restoration procedure to recommend, so this guide doesn’t ask you to rename or overwrite active saves.

Verify installed files if the updated game still crashes

After the game-specific fixes, Steam’s file verification is a reasonable next step for persistent crashing or missing content. It checks the installation; it is not the same job as recovering a world save.

Valve’s verification instructions ↗ (opens in a new tab) use this route:

1. Restart your computer and launch Steam.
2. In your Library, right-click Moon Sweepers, or use the gear icon on its Library page, and select Properties.
3. Open Installed Files, then choose Verify integrity of game files.
4. Let verification finish. Valve says it may take several minutes; don’t verify several games at once or run other system-intensive tasks alongside it.

Valve also notes that some local configuration files can fail verification normally because those files should not be replaced by the process. That notice doesn’t make every validation failure harmless. Keep the distinction between installed files, local configuration and world backups instead of treating them as one folder to delete.

Once the world runs, solve the problem you still have

For a persistent fault after the relevant updates, the developer asks players to use its official Discord ↗ (opens in a new tab). A short description of the action that still fails is more useful than another speculative system change. Keep the available world backups intact while you follow up.