Hi Quentin Kefford,
Welcome to Microsoft Q&A Forum, thank you for posting your query here!
It seems you’ve encountered an issue while composing models in Document Intelligence Studio. The error message stating that a classification model is needed indicates that the composed model feature now requires a separate classification model to combine extraction models.
The latest version of Document Intelligence Studio mandates an explicitly trained classification model to determine which extraction model, such as 1040 or 1099, applies to a document. To resolve this, ensure the classification model is compatible and meets the requirements. After training the classification model, integrate it with the extraction models to route documents appropriately.
Start by training a classification model using the 1040 and 1099 datasets, then compose the models in Document Intelligence Studio by selecting the trained classification model along with the extraction models.
please check the below similar thread for reference.
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