# Troubleshoot security configurations

Identify and resolve issues with your security configurations by diagnosing common problems related to setup, coverage, and license availability.

## Links

* [A repository is using advanced setup for code scanning](/en/code-security/reference/security-at-scale/troubleshoot-security-configurations/a-repository-is-using-advanced-setup-for-code-scanning)

  You see an error when you try to attach a security configuration with default code scanning enabled to repositories that use advanced setup for code scanning.

* [A feature has disappeared from a security configuration](/en/feature-disappears)

  Changes to your GitHub Enterprise Server instance's installation settings by a site administrator may affect which security features are available to your configuration.

* [Default setup for code scanning overrides advanced setup](/en/code-security/reference/security-at-scale/troubleshoot-security-configurations/unexpected-default-setup)

  You apply a security configuration with "Enabled with advanced setup allowed" and the existing advanced setup for code scanning is ignored in some repositories.

* [Finding and fixing configuration attachment failures](/en/code-security/reference/security-at-scale/troubleshoot-security-configurations/finding-repositories-with-attachment-failures)

  You can identify any repositories where the security configuration could not be attached, and follow guidance to remediate the problem.

* [Not enough GitHub Advanced Security licenses](/en/code-security/reference/security-at-scale/troubleshoot-security-configurations/not-enough-github-advanced-security-licenses)

  If you are on a subscription-based billing model for GHAS, you need available GHAS licenses to enable GHAS features on a private repository.