Difference between InfoPath preview and InfoPath form in production

Hey all,

A couple months ago we developed a cascading drop down function in the C# code behind our infopath webform. There is 1 master field (a dataconnection to a SP list) and 1 slave field (dataconnection to a SP list). So when a user selects a value in the master field, only the corresponding values to that master value appear in the slave field. The weird thing was, everything worked fine in the infopath Preview mode. But when we published and activated the form template to our site, it did not work anymore. After analyzing the code we knew that the problem was somewhere in InfoPath. And so we stumbled upon the properties of the 2 fields in InfoPath :-).
When you double click the field in InfoPath you will see a tab called 'Browser Forms'. By default, the postback setting is set at 'Only when necessary for correct rendering of the form)'. Unfortunately this setting did not work for us in production so we changed it to 'Always'. This finally solved the problem. Hopefully this could help any of you in the future.

Thibaut