DocumentationExperience Cloud KCS

AEM Sites: Resolve 500 error when creating a launch on pages with inconsistent Live Copy configuration

Last update: July 27, 2026

This article explains how to resolve a 500 Internal Server Error that occurs when creating a launch for a page in Adobe Experience Manager (AEM) Sites due to inconsistent Live Copy metadata. The solution involves correcting the Live Copy configuration on the affected page.

Description description

Environment

Adobe Experience Manager (AEM) Sites, all supported versions and deployment models (on-premise, Adobe Managed Services, and AEM as a Cloud Service).

Symptoms

  • When attempting to create a launch for a specific page, the operation fails with a 500 Internal Server Error if using the REST API, or a Failed to submit form error in the AEM UI.
  • The issue is isolated to certain pages; other pages allow launch creation without error.

Cause

This error occurs when the page’s Live Copy configuration is incomplete: the jcr:content node contains a cq:LiveSyncConfig node (indicating a Live Copy relationship), but the required cq:LiveSync mixin type is missing from the jcr:mixinTypes property. This inconsistency prevents AEM from properly handling Live Copy state during launch creation, resulting in a 500 error.

Resolution resolution

Follow the steps below to resolve the issue:

  1. Attempt to create a launch for the affected page using the AEM UI or REST API to confirm the error occurs.

  2. Inspect the Live Copy metadata on the affected page:

    • Open CRXDE Lite (or your preferred repository browser) and navigate to the jcr:content node of the affected page.

    • Verify that a cq:LiveSyncConfig node exists under jcr:content.

    • Check the jcr:mixinTypes property on jcr:content and see if cq:LiveSync is missing.

  3. If cq:LiveSync is missing from jcr:mixinTypes, add it:

    • In CRXDE Lite, select the jcr:content node.

    • Edit the jcr:mixinTypes property and add cq:LiveSync to the list of mixin types. Save your changes.

    • Alternatively, use a repository API or a POST request to update the property. For example (replace placeholders with actual values):

    code language-none 
    curl -u : -X POST "https:///content//jcr:content" \
-d "jcr:mixinTypes=" \
-d "jcr:mixinTypes=cq:LiveSync" \
-d "jcr:mixinTypes@TypeHint=Name[ ] " \
-d "charset=UTF-8"

Ensure you include all existing mixin types in your update.
4. Retry launch creation for the affected page. It should now succeed without error.
5. If other pages exhibit the same symptoms, repeat steps 2–4 for each affected page.

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