JSI Tip 9792. The KB906569 update adds the Tools tab to the System Configuration utility (MSCONFIG.EXE) in Windows XP Service Pack 2.

Microsoft Knowledge Base Article 906569 contains the following introduction:

This article describes the new Tools tab that is available in the System Configuration utility (Msconfig.exe). The new Tools tab is available after you install the KB906569 update on a Microsoft Windows XP Service Pack 2 (SP2)-based computer.