Issue

The environment fails to start after a deployment. The following error appears in the logs:

ERROR - Core: Failed to load model: Missing microflow constant definitions. 
com.mendix.m2ee.api.InfoAdminException: Missing microflow constant definitions.

This article will cover why this error occurs and how it can be resolved.

Environment

Applications hosted in Mendix Cloud

Cause

The application model includes microflow constants that are not defined in the environment configuration. During deployment, the runtime requires all referenced constants to be present and correctly defined.

If any of these constants are missing, misnamed, or contain formatting issues (such as extra spaces or missing module prefixes), the environment cannot load the model, and the deployment fails. This results in the environment throwing an error and failing to start after the deployment attempt.

Solution / Workaround

To resolve this issue for the Mendix Cloud environments, verify and correct the microflow constant definitions in the affected environment by following these steps:

1. Navigate to the Environments tab of the affected application in the Mendix Portal.

2. Select the environment that is failing to start and click on Details.

3. Go to the Model Options tab within the environment details.

4. Under Constants, review all microflow constants currently defined for this environment.

5. In Mendix Studio Pro, open the App Explorer and check each module’s Constants folder to identify which constants are used in your project. Ensure that:

   • All required constants used in the application model are present.

   • Constant names match exactly, including correct casing and any module prefixes.

   • There are no leading or trailing spaces in constant names or values.

6. If any constants are missing or incorrectly defined, add or correct them in the environment configuration.

7. After updating the constants, redeploy the application to the environment.

Additional information

• Mendix documentation:
  • Constants
  • The Model Options Tab