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The upload control is not currently fault tolerant. Uploaded file attachments are only stored with the node that processed the upload. If the node that is processing your form instance shuts down, all attachments are lost. The user will notice this only If the user refreshes the form or tries to add/delete another attachment. In this case the upload control is refreshed and the current state of all prior attachments having been removed becomes visible. If the user does not refresh the form or add/delete another attachment the form will continue to show the lost attachments. However when the form is submitted they will not be part of the submission. This out of sync behavior will be addressed in a future software update.
A second scenario is a form that is ready to submit as all required fields are filled and a required upload control (max=1) has an attachment already uploaded. If the node processing this form instance shuts down and the next action on the form is the user clicking the submit button, the user will see the form refresh because the upload control attachment was deleted and the form requires an attachment. The form will refresh to its orginal UI state meaning the Section controls and Tabs will go back to their initial selected/expanded states. This may seem odd to the form user. At this point all the user has to do is to re-upload the attachment and submit the form. The UI state going back to the default will be improved in a future release.
Trying Templates
Trying form templates from the Templates menu are not fault tolerant. If you are trying a form template and the node the form instance is running on fails, the form will not continue operating propertly. This is a temporary limitation and may be lifted in a future release.
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