Windows Update Agent downloaded and installed itself automatically

Today I noticed that Windows Update looks different (larger icons – different UI). It was strange, because I didn’t installed any updates and I have selected ‘Check for updates but let me choose whether to download and install them’ under ‘Change Settings’ under ‘Windows Update Control Panel’.

I searched web and found that this have happened before for ‘Windows Update Agent 7.2.6001.784’ and now for ‘Windows Update Agent 7.4.7600.226’. This proces is explained in Microsoft Update Product Team Blog post Upcoming Update to Windows Update dated 2008/07/03.

Occasionally, we must update the infrastructure of Windows Update in order to ensure a high level of service quality, reliability, and operation.

Anytime the Windows Update agent is turned on, Windows Update will take care of updating itself. Windows Update is considered “on” when anything other than “Never check for updates” or “Turn off Automatic Updates” is selected. What this means is that if you’ve selected “install updates automatically,” the update to the Windows Update client will install automatically. You may also notice that Windows Update will also automatically download and install updates necessary for the Windows Update client to function properly if you’ve chosen a different setting, like setting 2 (“Automatically Download Updates”) or setting 3 (“Automatically Check for Updates”). This is done in order to ensure that a system will continue to notify the user about available updates.

The Windows Update client does not download or install infrastructure updates if the user has selected setting 4 (“Off”). In other words, if a Windows Vista user selects “Never check for updates,”( or if a Windows XP user selects “Turn off Automatic Updates”), the user will not receive Windows Update client infrastructure updates unless they choose to manually install it from Windows Update.