"'SnippetElement' is null or not an object" error when submitting InfoPath 2010 form

I have an InfoPath 2010 web form that was upgraded from a 2007 version. The 2007 version worked fine.

When the form submits, it saves to a SharePoint 2010 document library - it is being saved correctly.

However, I get a javascript error, "'SnippetElement' is null or not an object". I've checked all my submit options and they look OK. Even republished the form several times to no avail.

Anyone had this error before 开发者_运维问答and can tell me how to stop it?

For anyone who comes across this post, I eventually solved the problem (though I think there is a bug in Infopath or SharePoint that caused the issue).

My form, and several others I have found since were using a "Submit" action to post the data to the list.

By changing the form to using a "Rules and Custom Code" action that is configured to submit using a data connection instead, the JavaScript error no longer occurs.

As these forms worked in 2007, clearly something has changed in 2010 that breaks them.