If you are running OEM software, you must authenticate both the connection and the database. If the database is not authenticated and it is running on a OEM engine, there is no grace period - any write operation against the database will result in an -98 Authentication Violation error. If you leave database_authentication set, you are at least getting read-only access to the database,

To address this issue, you can use the InitString connection parameter. See Executing the authentication statement for a discussion in the context of authenticated applications.

Just to add to Chris's answer: In order to work with a MS Linked Server, I guess you will have to

• add the InitSting to the "Provider String" for the SQL Anywhere OLEDB provider you are using, or

• possibly by adding an OPENQUERY call the following with your according OEM string before you query the SQL Anywhere database (I'm not sure whether this does work as it would require that the Linked Server access does use the same database connection for both calls):

  SELECT * FROM OPENQUERY(<YourSAProvider>,
  'SET TEMPORARY OPTION connection_authentication=''company = ...'';')