Thank you for your inquiry.
Unfortunately, it is not possible at the moment , you can download only one archived envelope in one attempt . Of course, you can try to create a cycle and use our GroupDocs API to download these envelops programmatically . For it you should use ListEntities
method to get a GUID for each envelope and GetFile
method to download the envelope.
If you will have more questions please feel free to contact us.
Your Document Collaboration APIs
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