the grub manual says (about error #15):
"This error is returned if the specified file name cannot be found, but everything else (like the disk/partition info) is OK"...
it's most likely a grub configuration issue... but did you try re-installing grub form your boot floppy/cd to see if it works???
the way i see it you have two choices, try to fix the current configuration, or nuke it and re-install grub, and if you re-install grub and it still doesn't work, well then we're back to choice one...
(of course there's always LILO)
=)
it would help us help you if you'd post some technical data, like your grub configuration, for example... also, the output of "df -hT" and "fdisk -l", among others...
here's some other links that seem to be useful for you:
http://linux.about.com/library/bl/di...t_inst3.20.htm
http://www.rocklinux.net/people/rene/drock/grub.html
http://forums.devshed.com/t49841/s.h...otup+LILO+grub!
http://www.linuxselfhelp.com/gnu/gru...ub_3.html#SEC9
http://sdb.suselinux.hu/en/sdb/html/..._overview.html
http://archive.linuxfromscratch.org/...er/029502.html
http://archives.linuxfromscratch.org...er/010650.html