Removing Duplicate Entries

No Duplicates option did not work for me. Did throw an error on the fronted but after a double click there was still two entries on the backed.

I solved the issue by tossing this jQuery function at the end of my footer.php

It simply says, when any form on the site is submitted, disable the submit button.

<script type="text/javascript">
	$("form").submit(function() {
		$(":submit").attr('disabled', 'disabled');
	});
</script>

If you only want to disable one form using this method you can do it one of two ways. 1) Create a WordPress page template for your form page and include the JavaScript above or 2) you can disable a signal form global by including the forms HTML ID instead of the general form element like this:

<script type="text/javascript">
	$('#gform_2').submit(function() {
		$(":submit").attr('disabled', 'disabled');
	});
</script>