Problem with installation from DOS partition

Fri Oct 15 06:30:47 PDT 2004

Hellow! First of all sorry for my poor English...
My computer doesn't have a CDROM drive, so I decided to install
Freebsd 5.1 from DOS Drive. I created the directory C:\FREEBSD,
copied the contents of the installation CDROM there, then I made two
boot diskettes...
During bootstrap process the system recognizes my hard drive( ad0 ,Seagate
barracuda IV 7200 40 GB) and other my hardware.
I create the slices "/","/usr" and 200mb swap, then mount
corresponding filesystems.
In MEDIA list I choose DOS.
Everything goes well until the configuring ends and the message "Last
chance !.." appears.  After a few seconds the error message "Error
mounting /dev/ad0s1 on /mnt: no such file or directory" appears.
My hard drive is the "master" on first IDE-cable.
Can anyone help me with this problem?
Thank you for your attention!