Tom:
Thank you so much for the fix you suggested. It may not work for everyone, but it certainly did for me. Found your suggestion by chance; HP has not responded to previous notes I've sent them, and I've had the "installation cancelled" HP updates issue for some time.
Funny - this morning they sent me a fix to fix the "installation cancelled" issue, and IT was cancelled when I tried to run it. After applying your suggested fix, however, it and everything else installs fine.
Thanks again for taking the time to suggest the fix.