Why does my game crash on startup only for some players?

Almost always corrupted persistent data (a damaged or old-format save/config) or a platform/hardware difference. Your own config, save, and machine are fine, so you never hit it, but a player with corrupted data, a missing asset, or unsupported hardware does. Capture the crash from their machine, the trace usually points right at the failing load.

Why did my game start crashing on startup after an update?

Usually because the update changed the save or config format, and the new version's loading code can't parse data written by the old version, so it crashes reading it on boot (often a crash loop). The fix is to version your save/config format and migrate old data rather than rejecting it. A wave of startup crashes right after an update is the signature.

How do I find what's causing a startup crash?

Read the crash's stack trace, which for a startup crash usually points almost exactly at the failing operation (an asset load, a deserialize, an init call). Since you often can't reproduce a player's startup crash locally, capture it from their machine with a crash reporter that records the trace, device context, and build version automatically.

Why Does My Game Crash on Startup?

Quick answer: Your game crashes on startup because something it loads or initializes at boot is failing: most often corrupted save or config data, a missing or unloadable asset, or systems initializing in the wrong order. Since startup is a bounded sequence, the cause is almost always in that early load, and the crash's stack trace usually points right at it.

A startup crash means the game dies during boot, before the player ever reaches the menu. Because startup is a predictable sequence (initialize systems, load saved state and assets, set up rendering), the cause is almost always in something loaded or set up during that window, which makes startup crashes more diagnosable than they feel.

The Usual Causes

Startup loads a lot of state at once, and any of it can be the culprit. The most common cause is corrupted or unexpected persistent data, a save or config file that's damaged or in an old format, which the loading code chokes on. Next is a missing or unloadable asset the game assumes is present. Then there are initialization-order bugs, where one system runs before another it depends on is ready. And platform/hardware issues, an unsupported configuration or a missing runtime dependency.

A strong clue is whether it crashes for everyone or just some players. Crashing only for some players (but not you) usually means corrupted persistent data or a platform/hardware difference, since your own config and machine are fine. Crashing after an update usually points at a save/config format change breaking old data.

How to Tell Which Cause It Is

The stack trace from the crash usually identifies the cause directly, for startup crashes it tends to point almost exactly at the failing operation (the asset load, the deserialize call, the init function). Since you often can't reproduce a player's startup crash on your own machine (their data and hardware differ), you need the crash captured from their machine, with the trace, device context, and build version.

Bugnet captures startup crashes automatically with the stack trace, device context, and version, and groups them by signature, so you can see whether they share a cause (the same asset, the same config field) and whether they cluster on particular hardware. That's what turns 'crashes on startup for some players' into a specific, identified cause.

What to Do About It

Once you know the cause, the fix follows: load save and config data defensively (detect bad data and reset to a default rather than crashing, which also prevents crash loops), version your save format so old data is migrated not rejected, verify assets are actually in the build, and ensure init order respects dependencies. The principle is that nothing read at startup should be able to crash the game.

For the detailed fix steps, see our guide on fixing a game that crashes on startup. The key diagnostic insight is that a startup crash is bounded to the boot sequence, so capturing the trace from affected machines narrows it fast.

A startup crash is bounded to the boot sequence, usually corrupted save/config data, a missing asset, or init order. Capture the trace from affected machines and it points right at the cause.