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This is how you change the Oracle JDBC driver in Kettle. Replace files "ojdbc14.jar" and "orai18n.jar" in the directory libext/JDBC of your distribution with the files found in the $ORACLE_HOME/jdbc directory on your server or if the versions are different, with the JDBC driver that matches your Net8 client. For Oracle 11g the drivers are named ojdbc5.jar and ojdbc6.jar.
If you still have issues please remember that the DLL that Oracle uses to connect has to be in your path. If all else fails, try copying the ocijdbc10.dll (might be called different in different versions) to the libswt/win32 folder (or win64).
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