Neither the wired nor wireless will connect to internet (although both show as connected). After much Googling, I've narrowed it down to a corrupt Tcpip driver (Device manager, View, Show hidden Devices -TCP/IP Protocol Driver has the exclam mark next to it).
Have tried sfc /scannow, but being Media Edition it eventually asks for the second Pro CD which I do not have. I found the driver in C\Windows|System32\Drivers, but it cannot be deleted from there (I was going to paste a copy of a good version of the driver from another XP machine). This corrupt driver prevents the usual tricks of ipconfig etc from running.