Diagnostic recipes

On this page

Symptom	First evidence	Bounded next step
black screen at startup	Game Default Map and runtime log	verify cooked map and staged effective config
works in PIE, asset missing packaged	cook root and manifest	trace owning map/Primary Asset/rule; clean target cook
plugin module missing	target/module/plugin descriptor and binary	build exact target; remove editor-only/runtime mismatch
DLL/shared library missing	staged tree and OS loader log	declare `RuntimeDependencies`; verify architecture/search path
wrong config in package	staged effective ini/device profile	identify later hierarchy override; remove generated input
cook succeeds, stage fails	UAT phase boundary and staging manifest	inspect non-asset source path, permissions, disk, stale output
Shipping behaves unlike Development	logs via Test/diagnostic candidate	compare compiled flags, modules, config, timing, stripped tools
package unexpectedly huge	container/chunk/file size report	rank largest additions and duplicate chunk ownership
tiny change creates huge patch	retained base/delta manifests	inspect resaves, compression/encryption, shader order, tool changes
crash has unreadable callstack	build ID and symbol match	retrieve exact private symbols; never use rebuilt equivalents
clean machine will not launch	OS loader/prerequisite/platform log	verify prerequisites and loose runtime dependencies
device platform unavailable	SDK/toolchain/platform component status	install supported version and re-run platform validation

After each fix, rerun the smallest failing phase, then the complete clean artifact and acceptance suite.

Sources and version

Documentation target: Unreal Engine 5.8. Confirm behavior in your installed engine; no per-procedure test result is implied.

Canonical reference and AI copy

unreal-packaging-deployment/references/diagnostics-recipes.md