UE5.3 ExitCode=25

Yeah, the error is still not clear, as usually with these logs…

I can give you general tips that sometimes work:

  • Make sure there absolutely no assets referenced from a Developer’s folder. That can never be added to build and can cause this build crashes.

  • Try deleting your /Build /Saved /DerivedCachedata and /Intermediate from the root folder and regenerate visual studio project files. Sometimes corrupted data in these folders gets in the way of building.

  • Play your game in Standalone and keep an eye on the Output console for warnings and errors that might require fixing.

  • Rebuild completely instead of using the “Only cook new content” option to make sure it’s a clean build.

  • If you have any plugins in your project that you aren’t using, disable them.

  • Lastly, if nothing works, make a copy of your project and delete all your maps. Try to make a build with an empty map to see if you have any corrupted maps in your original project, or maps with missing or corrupted assets.
    There’s an old weird bug (from Unreal Engine 4) that would cause maps to duplicate and misreference themselves, making it imposible to build while hard to see any issues in the editor.

You can check that by looking at the “debug target” on your map’s level blueprint. If there’s more than one option without pressing play, that’s a big problem, cause as far as I know that can’t be fixed without deleting and creating a new map.