>>>>We had such problems before in my former job place. Once the file got locked, only re-booting the computer in question released this lock.
>>>
>>>We had to reboot a few times, too. At other times, I just boot the users (if a file called "maintenance.tmp" exists, the application quits automatically), but this doesn't always work.
>>>
>>>And, sometimes the problem disappears by itself after a few minutes.
>>>
>>>The problem is, this is happening almost every day, recently.
>>
>>What kind of file it is? Dbf?
>
>Yes, DBF. - As Borislav pointed out, if it is opened exclusively, then only one user has it open. Strangely, I hadn't thought about this.

I tried to tell you that in my first message, sorry if it was unclear. So, you resolved your problem?