At home totally manual - if it ain't broke... (and somehting to do with not wanting auto updates to break my WGA workaround

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In an enterprise environment updates should be manual - current financial institution I'm at has a regular monthly patching cycle for all it's severs (and desktops). And all updates are tested beforehand in the test environment.
Spinal - I'm assuming your course is not about home computing, so it's worth making the point that business have to protect against outages caused by "automatic" updates that could impact critical applications. Personally I'd fire any IT director of an SME or above that allowed automatic updates on their business critical systems.