With AcuXDBC created the system catalog without security, e.g. did not use the -pa option.
When accessing the tables from Microsoft Access a prompt with the User/Password dialog is always dispalyed. If they are left blank and enter is pressed it proceeds, so it does not need a username or password.
How can that popup be avoided?
The AcuXDBC driver is prompting because there is no username or password specified in the DSN.
Even though the AcuXDBC system catalog doesn't use security the driver can't know that before it connects. Since the username and password are empty it prompts for them.
The solution is to configure the DSN and add any value for Username and Password.