Windows 7’s Event Viewer includes a new category of event logs called Applications and Services Logs, which includes a whole host of subcategories that track key elements of the operating system. The majority of these subcategories contain an event log type called Operational that is designed to track events that can be used for analyzing and diagnosing problems. (Other event log types that can be found in these subcategories are Admin, Analytic, and Debug; however, describing them is beyond the scope of this article.)
Now, within the operating system section is a subcategory titled Diagnostic-Performance with an Operational log that contains a set of a Task Category called Boot Performance Monitoring. The Event IDs in this category are 100 through 110. By investigating all the Event ID 100 events, you will be able to find out exactly how long it took to boot up your system every time since the day you installed Windows 7. By investigating all the Event ID 101 thru 110 events, you will be able to identify all instances where boot time slowed down.
You can find and launch Event Viewer by opening the Control Panel, accessing the System and Security category, selecting the Administrative Tools item, and double-clicking the Event Viewer icon. However, you can also simply click the Start button, type Event in the Start Search box, and press Enter once Event Viewer appears and the top of the results display.
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