InfoPath Dev

Hi everybody, I´m new here and I hope to get some help for the following issue. I´m trying to make a Rest Web-Service call through a Browser enabled Form in SharePoint 2013. In client mode everything works just fine. But when i publish the form to the server it stops working. I´ve spent plenty hours in troubleshooting. By now without any success :( What I am trying to achive is to calculate the days betwenn 2 different dates (Therefore I stored the Excel-sheet in a library. I am using the networkdays formula which works great). As I said. Everything works fine, when I hit the preview button in InfoPath. I´m getting the following message in SharePoint: An error occurred querying a data source. XML data that is required for this form to function correctly cannot be found. The message in ULS-Log: The following query failed: REST Web Service (User: ... Type: DataAdapterException, Exception Message: The form cannot run the specified query. The remote server returned an error: (403) Not Allowed.) I already disabled the loopback check on the Windows server. Any idea how to solve this? Thanks and sorry for my weak english. Regards

Hi all, i could solve the problem. Maybe this solution helps somebody else. I modified the web.config of my web application. The AllwowAnonymousImperison key has to be changed from true to false. This cost me more than two days of troubleshooting. But now it is working :)