Can you boot to Windows XP?
If so, what error do you discover when you try to get to the Device Manager?
Are you going to Start -> Control Panel -> System -> Hardware -> Device Manager? If not, were does it stop along the way?
If using a telephone modem, what do you see when you go to Phone and Modem settings in the control panel, then to properties, then trouble shoot..
The 711 error can be a telephone modem error or a network connection error... but in either case it is usually a failed connection device.
However, it was also a very common SP1 error... Can we assume you have SP2, and all the updates, installed?