File locking not occurring as it should

Hi,

I have a bit of a strange problem. When i open a word document which is hosted on a file server cluster, Word does not show the traditional message about the file being locked if someone else has already got this file open. this is not an Office problem this is a file locking problem, let me explain the setup and the tests i have done.

firstly i have two file servers FS1 and FS2 which are part of a cluster, i have made a file server clustered role for general file server purpose called Cluster-FS, which has a disk resource formatted using ReFS, the disk is given drive D letter and is currently owned by FS1.

on two separate client workstations, i perform the following tests from both clients at the same time and have the following outcomes:

1. open the file \\Cluster-FS\Shares\Data\doc1.docx - both files open seamlessly with no warning about file locking, but in the title bar of one Word application it does state "read only" but the user has to pay attention to this
2. open the file \\FS1\D$\doc.docx - on the client which opens it last i receive the notification that the file is already open and i get the options whether to open it as read only, merge files later, or save a local copy - remember the underlying disk drive D is the same as point 1 above, it is formatted as ReFS but the very act of accessing it via the clustered role name produces a different outcome
3. open the file from \\FS\c$\doc.docx - on the client which opens it last i receive the notication that the file is already open, exactly like in point 2 above. the underlying disk is NTFS

from what I can tell this has nothing to do with the filesystem format, it is purely based on how the file is accessed, but why would accessing it via the clustered role name have a different outcome, in ALL tests i see the hidden lock file get created for the document, its just in test 1 above, it immediately opens it without warning. because of this, users dont pay attention to the small title bar which indicates the file is "read only" and when they come to save it, they are prompted to save as a different file name. you might think this is a trivial issue with a few Word documents, the problem is that when we open large design projects using SolidWorks which open many sub files, this causes a big problem when it comes to saving the files if someone else was modifying one of those sub files (sometimes from another geographical location so it's not even like they are sat next to each to tell each other what's being worked on). This problem only gets bigger as the team size is bigger.

am I missing some sort of setting for the clustered file service role to enable this kind of "file locked" notification? has anyone else noticed this?

thanks

Steve