Runtime And Bootstrap Errors

Common Symptoms

SymptomLikely causeFix
App starts on dev machine but not clean machineRuntime installed on dev machine onlyTest runtime deployment on clean Windows machine
Windows App SDK API fails earlyBootstrapper did not run before SDK APIInitialize bootstrapper at startup for unpackaged/external-location apps
Architecture-specific failureWrong x64/x86/arm64 runtime packageInstall matching runtime or use redistributable correctly
Self-contained output still missing behaviorFeature depends on additional package/serviceCheck self-contained docs and feature-specific dependencies
Runtime blocked during updatePackage in use or DDLM behaviorClose app and inspect deployment/runtime logs

Checks

Packaging model:
Runtime model:
Runtime installer used:
Architecture:
Bootstrapper call location:
First Windows App SDK API call:
Event Viewer/runtime log:

Recovery Path

  1. Confirm packaging model.
  2. Confirm runtime model.
  3. Confirm current runtime version from downloads page.
  4. Confirm bootstrapper or Deployment API path.
  5. Test on a clean machine.