GitHub Actions / GitHub Actions

GitHub Actions Self-hosted Worker Hangs Holding Runner Slot After workflow instance not found

Fix GitHub Actions self-hosted runner stuck in busy state after workflow instance not found error Includes evidence for GitHub Actions troubleshooting demand.

Category
GitHub Actions
Error signature
Self-hosted Worker hangs holding runner slot after CompleteJobAsync hits 'workflow instance not found'
Quick fix
Compare the failing environment with a known working setup, then change one configuration value at a time.
Updated

What this error means

Self-hosted Worker hangs holding runner slot after CompleteJobAsync hits 'workflow instance not found' is a GitHub Actions failure pattern reported for developers trying to fix github actions self-hosted runner stuck in busy state after workflow instance not found error. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub issue #4418 on actions/runner: self-hosted worker hangs holding runner slot after CompleteJobAsync hits ‘workflow instance not found’. Runner becomes permanently busy, blocking CI/CD pipelines for paid GitHub teams using self-hosted runners.

Common causes

Quick fixes

  1. Confirm the exact error signature matches Self-hosted Worker hangs holding runner slot after CompleteJobAsync hits 'workflow instance not found'.
  2. Check the GitHub Actions account, local tool state, and provider configuration involved in the failing workflow.
  3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

Step-by-step troubleshooting

  1. Capture the exact error message and the command, editor action, or request that triggered it.
  2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
  3. Review the source evidence below and compare it with your environment.
  4. Apply one change at a time and rerun the smallest failing action.
  5. Keep the working fix documented for the team or deployment environment.

How to prevent it

Sources checked

Evidence note: GitHub issue #4418 on actions/runner: self-hosted worker hangs holding runner slot after CompleteJobAsync hits ‘workflow instance not found’. Runner becomes permanently busy, blocking CI/CD pipelines for paid GitHub teams using self-hosted runners.

FAQ

What should I check first?

Start with the exact Self-hosted Worker hangs holding runner slot after CompleteJobAsync hits 'workflow instance not found' text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed GitHub Actions workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without Self-hosted Worker hangs holding runner slot after CompleteJobAsync hits 'workflow instance not found'.