Unable to upgrade from 8.2.2.5 to 9.1.0.0

Try these threads for ideas on what to investigate:

resource.dopus.com/viewtopic.php ... light=slow
resource.dopus.com/viewtopic.php ... light=slow
resource.dopus.com/viewtopic.php ... light=slow
resource.dopus.com/viewtopic.php ... light=slow