Last September, many Microsoft Windows users were distressed to find out that the Windows Update service was quietly updating itself on their systems—without any advance notice from Microsoft about the update. Apparently wanting to avoid springing another “silent” update on its customers, the Microsoft Update product team gave notice on July 3, via its blog, of an impending update to the Windows Update agent starting at the end of this month (see the blog post "Upcoming Update to Windows Update").

Michelle Haven, the Windows Update product manager who posted the blog, explained what changes the update will make to the Windows Update agent and what Windows Update settings will need to be in effect on users’ systems for the update to occur. Haven said that the main change that users might notice after the update is that Windows Update will probably take less time to scan for available updates.

Judging from comments on the blog, the most controversial part of the Windows Update updating process is that, unless the user explicitly turns off Windows Update, the updating process will occur without first requesting the user’s permission to do so. (You can change Windows Update settings via the Windows Update application in Windows Vista or the Automatic Updates Control Panel in Windows XP.) Although Microsoft is telling users about the update ahead of time, some IT people, understandably, object to what amounts to Microsoft modifying their system without their express approval.

Haven said that the Windows Update updating process is different from other types of updates to ensure that the Windows Update service is working correctly for customers. “The reason Windows Update issues infrastructure updates in this way is to ensure that users are able to successfully check for updates and/or receive expected notifications. If Windows Update wasn’t able to do this, it may cause some users to believe that they have all of the latest security updates, even though there was no installation and/or notifications of updates,” said Haven.

Haven said Microsoft will start rolling out the Windows Update updates at the end of this month through the next several months. You can find more information about Windows Update here.