Explorer Initialization Duration

Most Applicable to: Startup application developers

Relevant Assessments:

• Boot Performance (Fast Startup)

This metric captures the time from the end of the Winlogon phase until the Windows Shell (Explorer.exe) reports an initialized Start Screen. It includes the start of the userinit.exe process, which in turn starts Explorer.exe. It also includes the initiation of startup applications that are stored in RunOnce registry keys.

Typical Influencing Factors

In the absence of RunOnce applications, most of the time in this phase should be spent initializing the Explorer process. Explorer reads a number of libraries and data files into memory during its initialization process. Contending I/O from other running components can interfere with and delay this activity.

Analysis and Remediation Steps

Specific issues are usually generated for longer durations of the Explorer Initialization phase. You can gain more insight by opening WPA to the time interval of the Explorer Initialization activity. Avoid placing applications in the RunOnce key on a recurring basis because it delays Explorer Initialization.

Investigating specific issues during Explorer Initialization is beyond the scope of this document. For a list of common best practices, see Best Practices for Time-Critical Tasks in the Results for the On/Off Assessments topic.