Error 21776 and dbo Problem

Hello:
We recently installed a SQL 2000 version of an older
application we were running. The company took our old
Paradox data and converted it at their site and gave us a
backup to restore to a new database we created on our SQL
server.
After restoring the database, we began to get Error 15023
messages relating to the user and login that the
application uses to grant access to the database. After
some research, I used query analyzer to drop the
questionable users and logins and then re-created them
without a problem. However, we were still getting errors
when trying to connect to the database using the
application.
While troubleshooting the problem, I went to look at the
properties of the sa account and the system threw up
Error 21776-The name dbo was not found in the users
collection. If I try to add a dbo user account to the
database in question, I get Error 15023. I can't drop
and re-create the users and logins because SQL is telling
me I can't do this with a database owner. I can't use
sp_change_users_login because it involves the dbo account.
I don't know where to go from here.
Any comments or suggestions would be appreciated.
Thanks
BrennanHave you checked this article?
305711 BUG: DBO User Does Not Display in Enterprise Manager
http://support.microsoft.com/?id=305711
Thanks,
Kevin McDonnell
Microsoft Corporation
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