It means you didn't followed the instructions how to get Daggerfall running to the letter, that's why you get errors.
In other (not so friendly) words: you screwed up.
As Daggerfall is a really nitpicking game to get to run in dosbox, it's not possible to tell you were you went wrong without a long and detailled list of what you have done till now.
But luckily for you you can download a ready to run package to use with dosbox frontend DBGL@
http://members.quicknet.nl/blankenda...chivesdownload