How to Fix Built-In Connectors Not Loading After Upgrading Azure Functions to v4+

If you’re looking to upgrade the “AzureFunctionsJobHostextensionBundleid” for your Logic Apps and want to keep all built-in connectors working smoothly, here’s a simple step-by-step guide to help you do it correctly.

First, understand that the extension bundle ID controls which version of the extension bundle your Logic App uses. Originally, you might have had it set to [1.*, 2.0.0), which allowed a flexible range of versions. When you updated the “extensionBundle__Version” in your environment variables and the host.json file to [4.0.0, 5.0.0), the built-in connectors stopped loading.

This happens because newer versions of the extension bundle might have compatibility issues or require additional configuration. If you’re encountering errors like missing connectors or failure to load components, here’s what you can do:

1. Restore the Previous Version:
   Revert the “AzureFunctionsJobHostextensionBundleid” back to the older version range, such as [1.*, 2.0.0). This helps ensure compatibility with your existing setup.

2. Update the Version Carefully:
   Instead of jumping straight to a higher version like 4.x, check the official documentation for the supported versions of the extension bundle for your specific Logic App runtime.

3. Update Configuration Files Properly:
   Make sure your “host.json” reflects the correct version range. For example:

   json
   {
   “extensionBundle”: {
   “id”: “Microsoft.Azure.Functions.ExtensionBundle”,
   “version”: “[1.*, 2.0.0)”
   }
   }

4. Verify Environment Variables:
   In your environment variables, set the version as needed, matching what’s in your host.json.

5. Test After Changes:
   Deploy the updated configuration and test the Logic App. If the built-in connectors load properly, then you’re set. If not, review the error messages or logs for clues.

6. Consult Documentation and Support:
   For newer versions, always review the official documentation or reach out for support to understand any required additional setup or breaking changes.

By rolling back the extension bundle to a compatible version, you typically restore the connectors’ functionality. When you’re ready to upgrade, do it gradually, verify each step, and always keep backups of your existing configuration to prevent service disruptions.

This approach helps ensure your Logic App continues to work smoothly while adopting new features or updates.