SMB connection "HANG"

I'm using open-e DSS lite server with HW Raid for storing roaming profiles. Now there is about 70 users on that server. All users are using workstations with Windows XP SP2. There is plenty of room on NAS ...

For some users sometimes roaming profile can't be copied from server. They are logging with temporary profile.
In workstation error log I got error that some file named prf*.tmp can't be copied from server because of some other process is using that file. I can't delete that file from any workstation because it is in use. Explorer even hang when I try to delete it.
On server Status → Connection → Active SMB user connections user is still connected even if I shutdown the workstation.
I try to reset NAS connection (Maintenance → connection → NAS connection reset → Reset SMB connection) but user is still connected to resource.
I must reboot entire DSS server to disconnect such user!
After reboot I can delete prt*.tmp and user can log normal with roaming profile.

It looks that on DSS server user connection “hang” on that file. Of course rebooting server is not solution I would like to do if this happen.

Some days ago I also write that on Roaming profiles share on DSS server Offline caching is enabled. I would like to turn this off. Error from event log “Windows has detected that Offline Caching is enabled on the Roaming Profile share - to avoid potential profile corruption, Offline Caching must be disabled on shares where roaming user profiles are stored. “

BTW. I'm using Model: Data Storage Server Lite, Version: 5.0.DL37000000.3003, Release date: 2008-01-31

With regards,
Dussan