[Samba] XP clients regularly lose connection

[Adrian Bolzan]

Hi,

We have Samba 2.2.8 on RedHat 9.0 (from rpm).
We connect about 5 Win XP Professional PC's (with Service Pack 1) 
to the server.  
Roaming profiles are set up.

After about 30 minutes client connections are lost to the server and 
the users cannot reconnect to the server, even if samba is restarted.  
A reboot of the server is required.

This occurs, it seems at this stage, when large files are copied across 
the network from the server to the workstations.  Such files include 
MYOB databases, and other files over about 50 MB.

(MYOB data directories are mapped to drives, and not UNC.)

Thanks,
adrian

Our smb.conf file is:

---------------------------------------


#
#======================= Global Settings 
#=====================================
[global]
   workgroup = tucksgrp
   netbios name = tuckssvr
   server string = Samba Server
   printcap name = /etc/printcap
   load printers = yes
   printing = cups
   guest account = smbguest
   log file = /var/log/samba/%m.log
   log level = 2
   max log size = 0
   security = user
   encrypt passwords = yes
   smb passwd file = /etc/samba/smbpasswd
   unix password sync = Yes
   passwd program = /usr/bin/passwd %u

   passwd chat = *New*password* %n\n *Retype*new*password* 
%n\n
   *passwd:*all*authentication*tokens*updated*successfully*

   pam password change = yes
   obey pam restrictions = yes

   socket options = TCP_NODELAY IPTOS_LOWDELAY  
SO_KEEPALIVE SO_RCVBUF=8192 SO_SNDBUF=8192

   local master = yes
   os level = 64
   domain master = yes 
   preferred master = yes
   domain logons = yes
   domain admin group = root @admins
   logon script = logon.bat
   logon path = \\tuckssvr\profiles\%U
   logon home = \\tuckssvr\%U
   logon drive = Z:
   wins support = yes
   dns proxy = no 
   oplocks = no
   kernel oplocks = no


#============================ Share Definitions
#==============================
[homes]
   comment = Home Directories
   browseable = no
   writable = yes
   valid users = %S
   create mode = 0664
   directory mode = 0775

 [netlogon]
   comment = Network Logon Service
   path = /home/netlogon
   guest ok = yes
   writable = no
   share modes = no

[profiles]
    path = /home/profiles
    browseable = no
    create mode = 0600
    directory mode = 0700
    guest ok = yes
    read only = no
    profile acls = yes
    csc policy = disable

[shared]
   comment = Public Stuff
   path = /home/shared
   public = yes
   writable = yes
   force group = tucks
   printable = no
   write list = @tucks
   create mode = 0660
   directory mode = 0770

[company]
   comment = Company Directory
   path = /home/shared/company
   public = yes
   writable = yes
   force group = tucks
   printable = no
   write list = @tucks
   create mode = 0660
   directory mode = 0770

[myob]
   comment = MYOB data
   path = /home/shared/myob
   public = yes
   writable = yes
   force group = tucks
   printable = no
   write list = @tucks
   create mode = 0660
   directory mode = 0770

[printers]
   comment = All Printers
   path = /var/spool/samba
   browseable = no
   guest ok = no
   writable = no
   printable = yes

---------------------------------------------