API Error When Submitting To A Form


We are receiving the following HTML error when making a POST to the following URL: https://forms.hubspot.com/uploads/form/v2/3938217/ac6763b4-6f7d-

<div class="outer-container">
   <div class="inner-container">
      <h1>You cannot submit to this form</h1>
      <h3>If you're the owner of this website:</h3>
      <p>You cannot submit to this form <em>(ac6763b4-6f7d-<Form GUID Truncated>)</em> because it is not a standard HubSpot form. </p>

What can be done to resolve this?


Hey @wdc, Looks like this form in your portal here: https://app.hubspot.com/forms/3938217/editor/ac6763b4-6f7d-4c11-b003-bf2bf625507f/edit/form, is not a HubSpot form. It's called #gform_1. Submitting via the HubSpot API to a non-HubSpot form will not work. You'll need to copy that form into HubSpot by clicking on the title in Forms Home, then embed that form into your external site.


Please excuse my ignorance, but we have been using this API call for over 25 months, having created thousands of Contacts with it.

Has something changed with this form, recently, that would cause an inconsistency all of a sudden?


Moreover, the last time we successfully used this endpoint was 2018-09-18 11:51:33.


Hey @wdc, apologies here, I may have jumped the gun on this one. We are making some structural changes to forms, but I'm going to reach out to my team about this to get some more context and see if this issue you're having is related. I'll reach out here when I have found out more information.



All of a sudden, these form submissions have started to work. It would appear that your changes have been successful.

Did anything in particular change?

Thanks again for your help!


Hi @wdc, that's interesting - nothing changed that I currently know of, but I've reached out to the Forms team already who can confirm. I'll definitely let you know what they say, as the error certainly could be the result of a structural change, but will let you know more info when I have it