Operation errorObject reference not set to an instance of an object.

Question

Why do I get an operation error when I am trying to create/modify users?

Symptoms

Similar to:

Operation error
Object reference not set to an instance of an object.
Sentinel.Ranger.RAM.Client.OperationException: Immediate command returned an exception ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at Sentinel.Sys.DirectoryServices.Path..ctor(String pathStr)
   at Sentinel.Sys.DirectoryServices.ActiveDirectoryManager.findGroups_(DirectoryEntry containerEntry)
   at Sentinel.Sys.DirectoryServices.ActiveDirectoryManager.findGroups_(Path path)
   at Sentinel.Sys.DirectoryServices.ActiveDirectoryManager.FindGroups(DomainName domainName)
   at RAM_dc.a(ActiveDirectoryManager A_0, GetUsersCommand A_1)
   at RAM_dc.a()
   at RAM_bp.e()
   at RAM_az.g()
   at RAM_b7.a(RAM_cu A_0)
   at RAM_b7.b(RAM_cu A_0)
   at RAM_a2.d(Job A_0)
   --- End of inner exception stack trace ---
   at Sentinel.Ranger.RAM.Client.CommandProcessor.submitImmediate_(ClientCommand clientCommand)
   at Sentinel.Ranger.RAM.Client.CommandProcessor.Execute(ClientCommand clientCommand)
   at Sentinel.Ranger.RAM.Client.CommandConnection.syncExecute_(ClientCommand clientCommand)
   at Sentinel.Ranger.RAM.Client.CommandConnection.GetUsers(UserFilter filter)
   at Sentinel.Ranger.RAM.Client.DataModel.GetUsers(UserFilter filter)
   at Sentinel.Ranger.RAM.Client.Host.RAMMainFrm.control_IdentitiesRequired(Object sender, GetIdentitiesByFilterEventArgs e)
   at Sentinel.Ranger.RAM.Client.CommandCentrePlugin.TextualSecurityIdentitySelectionControl.processText_()
 

Cause

This is proved to be caused by any OU or Group Names with Active Directory Users & Computers containing a "/" anywhere in the name.

Resolution

Renaming the OU or Group Names to be without the "/" seems to resolve the issue.