"The module ... owssvr.dll could not be loaded due to a configuration problem"

Recently, one of my teammates installed ArcGis Server 9.3 on our fresh SharePoint 2010 box, causing all sites to respond with 503 Service Unavailable. A quick inspection showed that the application pools have stopped themselves, and the Windows application event log was spammed with:

Event ID: 2282
Source: Microsoft-Windows-IIS-W3SVC-WP ...
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