Found the answer, and you'll never guess what was responsible.
Yes Regional Settings, there are Dark Forces at work here.
I live in the United Kingdom, and accordingly set my PC's regional settings to match that. With my regional settings set to UK, the game fails.
Set my regional settings to United States (US) Bingo!! I'm up and running.
Ah well, at least I'm online now, and ready to fragg.
Thanx for your comments guy's, as any light in the dark, is always encouraging.
I'll cancel my Live 5.1 card now I guess.