>>>Is there any way of telling which user on the network has a particular file open - we run overnight runs which pack and reindex the most important tables and they very often fall over because an unknown user has a file open
>>>
>>>Thanks
>>
>>
>>NetFileEnum api. For an example see faq#7790
>
>
>Also,
>
>Start | run | mmc
>
>File | Add Remove Snap-in | Shared Folders | Another computer | enter name or ip | Check: open files | ok

Thanks Gregory

I have already installed Sergey's answer and it works