Alan wrote:
>How can I determine what is causing a dialog box to appear at system star=
>tup saying "svchost cannot be found">>


When you open Task Manager, you'll see a number of "svchost.exe" running. 
This is normal.

These are applications ("Service Hosts") which run various groups of 
services.  Each instance of svchost.exe runs a different group of 
services.  It's not easy to determine which services are run by each of 
these files, without the help of 3rd-party utilities such as Process 
Explorer (freeware from www.sysinternals.com).

It seems that one of your startup processes--possibly hard-wired into XP--- 
requires a service which has been disabled or removed.

Go carefully through the Services and enable all services which might 
conceivably be useful, especially those you don't fully understand. See if 
that makes any difference.

If all is now OK, you can selectively disable some groups of services using 
trial and error, and a lot of patience, until you isolate the problem.

The other usual remedy is to do a repair install of XP, which might replace 
any missing services.

However, some software utilities can insert their own services into the 
system (not a good practice in my view, as it can cause the sort of 
problems you are now experiencing), so the problem could still be 
present.  Have you changed or removed any hardware or monitoring utilities 
lately? Possibly the service might remain but cannot find its parent.

Here's a list of services which can usually be safely disabled on the 
average single-user non-network home computer:

Alerter
Clipbook
Computer Browser
Fast User Switching
Human Interface Access Devices
Indexing Service (Slows the hard drive down)
Messenger
Net Logon (unnecessary unless networked on a Domain)
Netmeeting
Remote Desktop Sharing (disabled for extra security)
Remote Desktop Help Session Manager (disabled for extra security)
Remote Procedure Call Locator
Remote Registry (disabled for extra security)
Routing & Remote Access (disabled for extra security)
Server
SSDP Discovery Service (this is for the utterly pointless "Universal 
P'n'P", & leaves TCP Port 5000 wide open)
TCP/IP NetBIOS Helper
Telnet (disabled for extra security)
Universal Plug and Play Device Host
Upload Manager
Windows Time
Wireless Zero Configuration (for wireless networks)
Workstation


Don Penlington


 From the Beach at Surfers Paradise in sunny Queensland.
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