Hi Aidan, I've had problems with no network access for the last couple of weeks, just the red block being displayed for netework. I was going to try deleting all references in Program files, but then thought try a System Restore in Control Panel to 30/08/2013 when I know the network was working OK.
15 minutes later, I'm back on-line with network working fine - got to be worth a try for you also.
HTH
CGJon