error on login

we have a strange error on login as if the innovator does not fine the  ITEMTYPE and USER tables. when logging in the MS-SQL management studio with innovator user, the tables are there and we are able to see and update data... the configuration file seems to be correct because if we change the password or server to something that is incorrect, we receive another error logging to DB. I have no idea what can be the reason for this error. Tsahi