Cannot upload file in registration form

Hi,

I need the ability to allow a registrant to upload an image and it to be saved on the server for use at the event. I've added the field (i've tried image and file) and it displays on the form just fine. However when a user selects the image and hits upload. It seems to upload to the server but the field disappears on the form. When the user then submits the website produces a fatal error and the user cannot proceed.

The errors coming up in the log are:

1. When first uploading file (field disappears after upload)

Notice: Undefined index: registration_information in file_ajax_upload() (line 279 of /modules/file/file.module).

Notice: Undefined index: #suffix in file_ajax_upload() (line 288 of /modules/file/file.module).

2. On submitting the form

Notice: Undefined index: registration_information in commerce_registration_information_checkout_form_validate() (line 204 of modules/commerce_registration/includes/commerce_registration.checkout_pane.inc).

Notice: Undefined index: registration_information in commerce_registration_information_checkout_form_validate() (line 205 of /modules/commerce_registration/includes/commerce_registration.checkout_pane.inc).

Notice: Undefined index: registration_information in commerce_registration_information_checkout_form_validate() (line 289 of modules/commerce_registration/includes/commerce_registration.checkout_pane.inc).

EntityMalformedException: Missing bundle property on entity of type registration. in entity_extract_ids() (line 7707 of /home/tickets/public_html/includes/common.inc).

The files are actually uploaded to the server correctly.

I've checked permissions and tested file upload on other forms on the site and they all work well.

Thanks,