Incorrect installation (SB Live)

My SB Live! card is working fine (apparently), but the associated software
doesn't seem to think so.
On trying to run Audio HQ, I get the message "No audio device compatible
with this program can be found. Reinstall the card..."
In Creative Diagnostics, clicking the Wave, Record and CD audio tabs brings
up "Your audio drivers have not been installed properly. Please
reinstall..."
In addition, the MIDI tab says (amusingly) "You do not have Creative SB
Live! installed in your computer."
(I didn't discover any of this until I started investigating soundfonts.)

I went to the Creative site, downloaded and installed what looked like a
promising fix (LiveDrvUni pack). It made no difference.

I have Win2000, and the card model is CT 4830. Main problem is I no longer
have the original installation disk(s) - can I get the necessary software
elsewhere?
Would it be easier/cheaper to buy a new soundcard?

JonR