Thank you for reaching out to the Constant Contact Community. I hope you are doing well today and it's my pleasure to assist you.
That's a great question. At this time, uploading a document as a direct response is not an available feature. You can try linking a button or text link to an email address with a request for the customer to respond with the document. You can also have them download a document from the email and request they then email it over to you. I hope this helps you. If you have further questions, you can feel free to reach out to us here.
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