You use Microsoft SharePoint Designer 2010 to edit an InfoPath Form Web Part in an External list form.
You publish the form to a Microsoft SharePoint 2010 site.
On the external list page, you try to edit the InfoPath Form Web Part.
In this scenario, you experience one of the following symptoms:
You can edit the form and save changes that are made to it. However, the page that the form is located on does not reload and show the changes that were made to the InfoPath Form Web Part.
The Web Part Tools frame does not open, and you receive the following error:
The following file is not a valid InfoPath form template: http://SharePoint_Server_Path/Lists/List_Name.
This problem occurs when the Form Location property of the Web Part page uses an absolute path that points to the root site collection instead of to a relative path. For example, the error occurs when path resembles the following: