We have an InfoPath 2010 template based Form library in SharePoint 2010 - It's suddently stopped working and started saving forms as "xml" files and values are not getting stored in promoted list columns.
Observations:
1. InfoPath form contains Code - which manipulates certain SharePoint data and generates a dynamic file name and then saves it using Submit data connection.
2. Forms are submitted successfully - No errors in ULS log entries on errors (extra logging statements added from InfoPath Form Code)
3. On the Form Library - saved forms are shown as XML files (xml icon) and not able to open it in an expected way.
4. On verifing XML file - it holds the data entered
5. This issue happening for all the InfoPath form based libraries under a site collection
6. Tried Feature de-activation & activation processes, updating templates and publish, etc - but no results
6. If you publish a simple InfoPath form without Code - it works fine. Also created a InfoPath form with Code (with basic operations) - it didn't work with same behaviours as mentioned above.
7. No DLL dependency related issues identified as of now.
8. Checked also the possibility of Software Patches
9. InfoPath form is used a subsite
10. Sample forms and actual forms are working in STG environment.
11. Administratibe approved forms
12. Browser-enabled
It would be great help, if any of you can provide valuable suggestions or solutions on this issue. It's in PROD environment. Thanks in advance.