RE: Marketing Form which allows you to upload a file
Hi,
Fields included in marketing form are set up in Dynamics 365 Marketing as marketing form fields, which can be mapped to Contact or Lead entity.
It means that the marketing form can only create or update the record of Contact or Lead entity. However, there is a many-to-one relationship between Case entity and Contact entity. And most importantly, the marketing form does not support attachment submissions. So it is not recommended to submit a case with marketing form.
If you’d like to let users submit a case with attachment, the most recommended way is to submit through the Customer Self-service Portal.
Here is a documentation about how to manage cases in portal:
Manage cases in portals - Power Apps | Microsoft Docs
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Best Regards,
Nya