Did you follow the documentation
https://docs.mendix.com/appstore/modules/excel-importer
You need to configure the model reflection module too.
Hi Lars,
See documentation : https://docs.mendix.com/howto/integration/importing-excel-documents
It has steps to configure the excel importer in Mendix.
You have to Download the Excel Importer and Mx Model Reflection modules from the Mendix Marketplace.
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