Zapier - How to update a CMS item with an external file?

My site uses Zapier to create a CMS item upon submission of a form. It works fine.

I am updating the Zap so that the new item includes a placholder pdf in the two file fields. This is not working.

I have tried to 1) create a live item, 2) update a live item and 3) PATCH through Zapier Webhook. I have tried to create, update and patch from both my box account and my Airtable account.

My problem is that I don’t know how to identify the file for CMS to receive. Is it a URL, is it the name, is it multiple fields?

Postman shows that the field looks like this…

Has anyone had success updating a CMS item with external files?

Here is the Zap:

Here is my site Read-Only:

With the Webflow API, you have to pass a url and a name for the file field.

"report": {
  "name": "myfile.pdf",
  "url": ""

You mentioned your Airtable account? Are the files in Airtable?

Yes, the file is in Airtable, but ideally I’d like to pull the file from box. Using the template you provided, I tried the following…

But, still no luck.

According to the box developer guide,, I think I’m missing the Access Token, but I’ve tried numerous times to get the Access Token through an HTTP module in Integromat, and I’m missing something.

If you have any ideas, let me know.

The files have to be available at a public and unauthenticated URL for Webflow to be able to download it. You can’t give Webflow a URL to Box’s API because that needs your authorization token.

If your files are in an attachment field in Airtable, that will work because Airtable serves them publically, e.g.

You might want to checkout PowerImporter. It’s a tool I built that pulls your data out of Airtable and maps it to your Webflow CMS.