Windows machines unable to rename shared files

Greetings,

A client of mine has a Mac Mini running OS X Server 10.8.4 which was recently upgraded from 10.6 flavour of server. All had been working fine under 10.6.

There were a few glitches that we've dealt with but I've been stumped by an error that occurs for Windows machines connecting to the share points (SMB).

For my client his problem is that Windows programs that edit files on the share point cannot save the edited files (but can create a new file). My understanding of the save process is that there is an inherent rename/delete that takes place for an edited file.

Initially I thought that KB article http://support.apple.com/kb/TS4149 was the issue so I implemented the instructions but the symptoms continued.

I did some looking at ACLs and they all seem OK to my limited knowledge. eg.

group:managers inherited allow list,add_file,search,add_subdirectory,delete_child,readattr,writeattr,readextat tr,writeextattr,readsecurity,file_inherit,directory_inherit

I then tested for the problem myself via Windows Explorer - creating a new folder and trying to rename it - getting an error indicating the folder is open in another program.

Does this mean that the problem is actually related to locking in some way and not the permissions? I don't really know where to go from here!!

Any pointers as to how I should investigate further would be gratefully received :-)

Graham