[Samba] Samba on Solaris 7 exhibits slow performance when switch from SECURITY=USER to SECURITY=DOMAIN on WinXP clients

[Thomas G. Tri, P.E.]

Dear List:

I have a network (about 30 PCs) that was working fine using SECURITY=USER. 
Last weekend we switched over to take advantage of a Win2K server (recently 
added to the network) to be used as a PDC, Active Directory, etc. The 
network clients are a mix of WinXP, Win2K-SP3, and WinNT-SP5.

After the switch, the WinXP clients started experiencing a severe slowdown 
after a short period of time. The time before the symptoms occur varies 
from a couple of minutes to maybe an hour. If they reboot, the performance 
is again normal.

The slowness symptoms are exhibited as random, major delays in opening a 
Word doc or Excel spreadsheet, navigating with Explorer, etc. The 
application will load at normal speed, the document loads, but then the 
hour glass cursor will stay present for up to 20 or 30 seconds or more 
before control is returned to the user.

Any help / insight would be greatly appreciated!!!!!

Misc Info:
Running Samba 2.2.8 on Sun Ultra 2 server with Solaris 7.
Running ftp to retrieve files from the server show performance above 
9MB/sec on a 40MB file
Copying files from the server to the WinXP PCs seems fine.
Running Samba at debug = 2 for that PC shows normal file opens / closes.
Running Samba at debug = 3 shows a lot of info, but none discernable as a 
problem (I'm not a SAMBA expert, but have been using for some 6 or 7 years 
now.)
Using local, not roaming profiles.
Win2K Server on a P3-450MHz PC - sole purpose is as a PDC and a license / 
software metering server

Settings were for SECURITY=USER
[global]
         workgroup = SKEES
         log file = /var/opt/samba/log.%m
         max log size = 2000
         name resolve order = host wins bcast
         max open files = 1000
         socket options = IPTOS_LOWDELAY TCP_NODELAY
         os level = 255
         preferred master = Yes
         wins support = Yes
         kernel oplocks = No
         guest account = guest
         create mask = 0660
         directory mask = 0770
         force directory mode = 02000
         hosts allow = 192.168.254.
         hosts deny = 0.0.0.0/0
         short preserve case = No

Current Settings for USER=DOMAIN
[global]
         security = 
DOMAIN                                   <-----------------Added
         password server = *                     <------------------Added
         workgroup = NTDOMAIN            <--------------changed
         log file = /var/opt/samba/log.%m
         max log size = 2000
         name resolve order = host wins bcast
         max open files = 1000
         socket options = IPTOS_LOWDELAY TCP_NODELAY
         os level = 255
         preferred master = Yes
         wins support = Yes
         kernel oplocks = No
         guest account = guest
         create mask = 0660
         directory mask = 0770
         force directory mode = 02000
         hosts allow = 192.168.254.
         hosts deny = 0.0.0.0/0
         short preserve case = No
         encrypt passwords = yes         <----------------Added