After successfuly upgrade to DNN 4.8.4, when attempting to add or edit to the Documents 4.0.0 module, we receive the following error:

Error: Edit Documents is currently unavailable.
DotNetNuke.Services.Exceptions.ModuleLoadException: Item has already been added. Key in dictionary: 'Administrators' Key being added: 'Administrators' ---> System.ArgumentException: Item has already been added. Key in dictionary: 'Administrators' Key being added: 'Administrators' at System.Collections.Hashtable.Insert(Object key, Object nvalue, Boolean add) at System.Collections.Hashtable.Add(Object key, Object value) at DotNetNuke.Modules.Documents.EditDocs.CheckRolesMatch(String ModuleRoles, String FileRoles) at DotNetNuke.Modules.Documents.EditDocs.CheckFileSecurity(String Url) at DotNetNuke.Modules.Documents.EditDocs.Update(Boolean Override) --- End of inner exception stack trace ---

Any suggestions?

In the portal root, all users have view folder permissions, with administrators only having write to folder permissions. 

All documents reside within folders in the portal root, with each folder having different a permission role with write to folder permissions.  So, for example, the Help Desk folder has view folder permissions granted to the Administrators, Employee and Help Desk Editor roles;  and write to folder permissions granted only to Help Desk Editor role.

This set up appeared to work until some documents were moved from one folder to another within the File Manager. 

I'm experiencing this same issue with Documents 4.1.  All folder permissions are set correctly.  Any help would be appreciated