isql and DataManager (in unixODBC 1.8.8 and prior versions at least) call SQLConnect passing a database username and password even if you do not specify them. isql, takes two optional arguments after the DSN which are the database username and database password. If you omit them then isql passes empty strings to OOB which believes a username and password were specified and hence does not pull the TargetUser and TargetAuth out of the DSN.
If your ODBC driver requires a username and password and you are using isql or DataManager you must specify them either on the command line or in the dialogue DataManager pops up.
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