How to prevent samba from holding a file lock after a client disconnects?

the below steps have helped me resolve this exact issue on a number of occasions:

1. Login to the samba server.
2. Run a “smbstatus”.
3. Find the pid of the process that has the lock on the file
   in the third section of the output.
4. Verify that it matches the expected user and hostname
   in the first and second sections of the smbstatus output.
5. Run “ps -ef” and see how long the smbd with that pid has
   been running.
6. If it has been running since before the computer was last
   rebooted, it’s a left over smbd. Kill JUST THAT ONE smbd.
   (And make sure you get the right one — it should be one
   that has a parent pid not equal to 1.)