Regardless of how you have decided to install OS X (Software Update, Delta, or Combo installers), you may run into a problem where the system might hang on installation. Though the occurrence of this with the 10.6.3 update seems to be rare, when it happens you may see it sit forever with the spinning color wheel, or go blank to a blue, black, or gray screen and require a forced restart. Even if the system appears to be healthy after the forced restart, there is the possibility that some files could be corrupt. As a precaution we recommend reapplying the combo updater.… Read more