Setting up Windows NT & Linux

I have NT on the first hard drive (hda1)and Linux v6.2 red hat on another(hdc1) hard drive.
After I had installed red hat I can’t access NT any longer and I tried the Red hat solution to have a dual O/S setup to no avail. But I must be doing something wrong here.i have edited ‘lilo’ configuration file and it looks good according to Red Hats solution and my manual.But No go.
It doesn’t even prompt me to boot NT either.
So I think I have to reinstall everything??
Thanks!