It should be a System DSN that is running wherever your ConnectionServer APS is running. Also, I'm assuming you are using the .accdb driver and not trying to use the .mdb driver.
It looks like you are using the 32-bit ODBC DSN (I think that's right for Access driver, maybe try x64 to be sure?) but you may want to make sure that the DSN name matches the one specified in your Universe connection.