My server crashed. How do I find out why?

When a server stops unexpectedly (not a clean shutdown or scheduled restart), Crash Doctor runs automatically and shows a diagnosis on the Console page.

It reports the exit code, a plain-English explanation, and a suggested fix. A few common cases it detects:

Exit code 137 means the server was killed for using more memory than your plan allows; either reduce memory usage (fewer addons/plugins, lower player-facing limits) or upgrade your plan.

Addon or plugin exceptions: for GMod, a Lua error that crashed the whole server rather than just logging; for Minecraft, an uncaught plugin exception. Crash Doctor names the addon or plugin where possible.

Port conflicts: another process already using the port the server tried to bind to.

Missing files: a required file (map, world, config) was deleted or never uploaded.

Crash Doctor only triggers on unexpected stops. If you stopped the server yourself or it restarted on a schedule, you will not see a report.