There any other field map layouts created for the same form that are failing. Deselect “Attach field to Email notification” on all other unused field map layouts then try again.

From the Field Map Layout screen, “Select the form to export data from:”
Then, one-at-a-time, select each of the test/unused layouts from the “Field Map to use:” dropdown, then un-check each of the email actions listed under the “Attach file to Email notifications” from the layout settings.

After confirming the above, if you still have the error, complete this form to allow us to take a look at your installation, or if not possible, then reply with the results of the above for further support.

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