Check Services ( services.msc ) → Look for your DB service (e.g., MySQL , SQL Server , PostgreSQL ). Start it if stopped.
The Query Engine requires specific .jar files to speak the database's language. If these drivers are missing from the server's library or are the wrong version, the connection will fail instantly. Check Services ( services
If you’ve exhausted the steps above and still see – especially if the error appears intermittently or after a recent Cognos upgrade – gather the following and open a ticket with IBM: Check Services ( services