What causes player settings resetting when a new build changes the prefs schema?

The new build reads settings keys or a layout that does not match what old installs wrote, so it falls back to defaults and discards the player's saved options.

How do I catch this when it only happens for some players?

Capture it automatically from the player's device with the full stack trace, the device and OS, the build, and a breadcrumb trail of what they did. That turns a vague complaint into a specific, reproducible issue you can fix without owning the hardware it happens on.

How to Fix Player Settings Wiping When a New Build Changes the Prefs Schema

Quick answer: Version your settings file and run a migration that maps old keys to new ones on first launch of the new build, instead of overwriting with defaults.

When an update renames keys or restructures the settings file, the game cannot find the old values and resets to defaults. A versioned migration preserves player choices.

How to fix it

1. Stamp a settings version

Store a settingsVersion integer in the file. On load, compare it to the current version to decide whether a migration is needed.

2. Migrate instead of defaulting

If the stored version is older, read the legacy keys, write them under the new keys, and bump the version. Only fall back to defaults when no file exists at all.

3. Keep old keys readable

Avoid deleting or renaming keys casually. When you must, keep a small mapping table so one update does not silently erase everyone's preferences.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.

Ship the fix, watch the signature disappear from the next build. That's how you know it's really gone.