Glenn,

Copied from Kelly's Korner no doubt.  ;-)

157. Prevent Automatic Folder and Icon Refresh - Enable
enableiconrefresh.reg

199. Enable Folder and Icon Refresh
disablerefreshundo.reg
http://www.kellys-korner-xp.com/xp_tweaks.htm

UpdateMode and NoNetCrawling have nothing to do with refreshing folders as
near as I can tell.  They may affect refresh, but I do not see how.
NoNetCrawling may free some things up if disabled.

HKLM\SYSTEM\CurrentControlSet\Control\Update\UpdateMode has to do with
Windows NT 4.0 System Policies.

UpdateMode
http://www.microsoft.com/technet/prodtechnol/windows2000serv/reskit/regentry/299
85.mspx?mfr=true

<quote>
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Update

Remote Update:
Category: Network
Subcategory: System Policies update
Selection: Remote update

Description: Controls how policies are applied to a Windows NT 4.0-based
computer.

Note The UpdateMode registry entry only applies for the Windows NT 4.0
policy.
<quote>
from...
How to apply System Policy settings to Terminal Server
http://support.microsoft.com/kb/192794

<quote>
By default, Windows NT is set to download and apply system policies. This
behavior is described in KB article 168231, "System Policies Are Not Applied
in Windows NT" at http://support.microsoft.com/?kbid=168231, and is
controlled by the following registry value:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Control\Update\UpdateMode (REG_DWORD)

* A value of 0 disables the application of system policies.
* The default value of 1 enables Automatic mode. Windows will look for the
Ntconfig.pol system policy file on the authenticating domain controller as
described previously.
* A value of 2 enables Manual mode. Windows will look at the NetworkPath
(REG_SZ) value (in the same key) and attempt to find the policy file located
there.
<quote>
from...
The Microsoft Windows NT 4.0 and Windows 98 Threat Mitigation Guide: Chapter
4 - Hardening Windows NT 4.0
http://www.microsoft.com/technet/security/guidance/networksecurity/legsgch4.mspx

<quote>
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Update
The following table lists valid settings for the UpdateMode DWORD value.

Setting    Description
  ----------------------------------------------------------------------
  0         System policies are disabled.
  1         Automatic mode. Search for a system policy file named
            Ntconfig.pol in the authenticating server's Netlogon share.
            This is the default value.
  2         Manual mode: Search for the specified system policy file in
            the location specified by the optional NetworkPath SZ value.

An UpdateMode data value of 2 requires an additional SZ value called
NetworkPath that specifies a local or network system policy path and file
name.

The following samples demonstrate valid entries for the NetworkPath value:
\\<Servername>\<Sharename>\<Filename>

  C:\<Directoryname>\<Filename>
<quote>
from...
System Policies Are Not Applied in Windows NT
http://support.microsoft.com/kb/168231

<quote>
UpdateMode value
This registry entry determines how the client will search for the
Ntconfig.pol file that contains the policies.
Path: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Update
Value name: UpdateMode
Data type: REG_DWORD
Values:

Value     Description
------------------
0      System Policies are disabled.
1      Automatic mode searches for a policy file that is named Ntconfig.pol
       in the authenticating server's Netlogon share. This is the
       default value.
2      Manual mode searches for the specified policy file in the location
       that is specified by the NetworkPath value. If UpdateMode is set
       to a value of 2, you must specify an additional value that is
       named NetworkPath that specifies a local or network system policy
       path and file name.

NetworkPath value
The NetworkPath setting is used to identify the location of the Ntconfig.pol
file that is used to determine System Policies if the UpdateMode value is 2.

Path: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Update
Value name: NetworkPath
Data type: REG_SZ
Values: Value Example
UNC path \\Server_name\Share_name\File_name
Local path C:\Folder_name\File_name
<quote>
from...
How to implement system policies for Windows XP-based, Windows 2000-based,
and Windows Server 2003-based client computers in non-Active Directory
environments
http://support.microsoft.com/kb/910203

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\
Explorer\Advanced\NoNetCrawling disables the net crawl functionality.
How to Disable Net Crawl Functionality
http://support.microsoft.com/kb/276322

NoNetCrawling is the state of the Automatically search for network folders
and printers option.

Folder Options | View tab | Automatically search for network folders and
printers

Automatically search for network folders and printers...
[[Specifies that Windows periodically search the network for shared folders
and printers. All shared folders and printers that are found appear in My
Network Places.]]

How To Disable Automatic Search for Network Printers and Folders in Windows
XP
http://support.microsoft.com/kb/320138

"Similar to a Web crawl, the net crawl feature searches out and provides
links to network resources."
from...
My Network Places "net crawler" functionality
http://support.microsoft.com/kb/256248

"NetCrawler checks for new resources whenever you log on to a network, and
whenever you open or refresh your Printers and My Net Places folders. It
doesn’t "crawl" in the following situations: when a Remote Access Server
(RAS) or Virtual Private Network (VPN) connection is active; when you are
logged on to a Terminal Server session; if your machine is a member of a
domain; or if the shell restriction "NoNetCrawling" is set."
from...
http://download.microsoft.com/download/2/e/0/2e0e3caf-9005-4058-b3e5-42432655b48
6/PRO/WindowsXPTechnicalOverview.doc

Thanks for the info. Unfortunately it didn't work for me. The first two
registry items were already set that way, setting the last had no
discernable effect (even after rebooting). Looks like I will have to put up
with the quirk.