Issue

When opening an upgraded application (to Mendix Studio Pro 9 or higher), an error pops up in Studio Pro:

Mendix.Modeler.Storage.Caches.TypeCacheUnknownTypeException: The type cache does not contain a type with qualified name Microflows$AppServiceCallAction.

Environment

Mendix Studio Pro v.9.1.0 and newer

Cause

The project contains App Services. App Services are removed from Mendix Studio Pro 9. Any project containing App Services in Mendix Studio Pro 9 will generate this error.

Solution/Workaround

Remove the App Services from the project and then upgrade the project (again).

If the error occurs after removing all App Services, then the App Services are still referenced in other parts of the project folder. Downloading a fresh copy of the project folder will resolve that. 

Additional Information

Mendix documentation: App Services