Assigning PWs to MySQL accounts

[seannnr]

I'm new to vBulletin, switching over to vB3 and assigning passwords to the MySQL accounts. I've got one box running the DB and two boxes running the vB3 application, all Windows boxes, and they connect using an ODBC connection. I created a new UN and PW for the ODBC connections and that all works fine, but if I assign a PW to the "root" user, host "%", the boards return a DB error and I can't post or anything. Is that the default, that the application will connect to the DB under that root user, and you can't secure it with a PW? Seems wrong of course, but I can't figure out why the application would use a different UN/PW than what I have set up for the ODBC connections.

Any ideas? Thanks!