The first thing YOU ARE COMPELLED TO DO is to read DOSBox readme file. In a nutshell: you need to mount as many drives as you need.

E.g.

mount c c:\ (for your hard-disk)
mount d d:\ -t cdrom (for an installation cd)

Another good idea is to SEARCH the forum. Bye.

I did search the forum and I wasn't able to find an answer for this specific problem in 80+ pages of posts.... I did however find a response on another forum to this exact problem.

All I had to do was PUT A CD IN! Doh! That simple. Now Ultima is installed on my machine, which was the first step that I was stumped on.

Thanks for your reply though! 😁

I don't think I was clear enough in my original post. I have the original game with the 6 3.5" floppy disks. I was trying to install the game using the Disk 1 Install program. When I did that, it told me "error reading Drive D" (the CD-Rom). Finding this forum was a godsend because I had pretty much given up in the past 9 months since getting this new computer on getting any of my old Ultima games to run!

This forum led me to the Exult forum which is where I found the answer to this problem.