After a migration from 2010 to 2013, within our many libraries, we have a column called Index that is a managed metadata column. The library is also grouped by theis column. What i have found is that i can view the library as normal and see all the grouped
documents by Index name as it should be. But our end users see one Index at the top of the library called Null (76) meaning 76 documents, the can be seen inside the index, but they are not grouped. I have shared the site with the employees group so everyone
has Contribute Permissions to the library.
dfrancis