[Zope] PB with zodbca object, very Important !!!!!!!!!!!!!!!!

When I create or use an object with a zodbc connection, and when I try to see a dtml page using it, zope open a login window (login with password) , but I don't know what it is, because I try lot of password (zope manager password, zope simple user password, Pc user password ....) no one can give me the access to the view of the dtml page. has anyone this sort of problem, and does anyone have a solution ???? thks a lot for your answer .... david sergent