Think I found the problem ...
Errors When Uninstalling Norton AntiVirus Software
http://www.bl.com/moshe/text/quiddit...on_errors.html
I uninstalled Norton Antivirus the other day and it turns it Norton doesn't uninstall completely - it leaves in some registry entries that prevent DHCP from functioning properly.
Big relief ... could also explain the blue screens I've been occasionally getting at startup.
Now I can back to work
Ron