Automatic updates require Windows 2000 SP3 or higher:
http://www.microsoft.com/athome/security/protect/update.mspx

I know that wuauclt.exe shows up in the task manager when it is running in the background and waiting for a response such as permission to download an update. You could check for that. I'm not sure what process is running during the download itself. Checkout the last link for debugging the windows update process. Of course, it depends on the configuration too. Are the systems configured to automatically download or to prompt for download or is it set to download and then install at a specific time or what?

These may be helpful:

http://support.microsoft.com/default.aspx?scid=kb;EN-US;327850
http://www.microsoft.com/athome/security/protect/update.mspx
http://www.winguides.com/registry/display.php/1003/

>Hi Tracy,
>Thanks for the response.
>Yes, I would like to detect it from within my VFP7 app, running on Windows 2000 workstations. ..And yes, I would like detect if the Windows Update is running, and possibly to determine if the update requires a restart.
>
>
>>Do I understand correctly that you want to check to see if windows update is running from within VFP7? What OS versions? I'm not sure the WUS works that way. Maybe the wus admin api? It's worth checking out though. What about checking if the windows update process is running?
>>
>>>Hi,
>>>
>>>Is there any way to detect a Windows Update in progress (allowing the app to complete its current processing and exit gracefully).
>>>Is it also possible to determine if the update will require a reboot?
>>>
>>>TIA