Does anyone know of a way, using nintex workflows (Or any other way) for a user to be able to download all of the contents of a document set into a zip file?
This can be accomplished using the PowerShell action: NTX PowerShell Action - Initial Beta Release
If you want this functionality to be used in Nintex Workflow, perhaps you need to write your own custom workflow action by using out-of-box feature supported by SharePoint to download document set as zip.
Kindly refer this two link for some code to re-use:
Download Document Set as zip – Chaks Corner
Create a SharePoint Custom Action to Zip and Download a Document Set - John W Powell - Site Home - MSDN Blogs
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