How to detect programmatically when the "Install Updates and shut down the computer" shield icon is present on top of the Start / "Shut down" button?

Question

Some updates put that little shield indicating that the computer needs to be rebooted. Is that shield a registry key? I thought it was the key:

HKLM\System\CurrentControlSet\Control\Session Manager\PendingFileRenameOperations

Source: http://technet.microsoft.com/en-us/sysinternals/bb897556.aspx

But my computer is showing the icon right now, and there is no PendingFileRenameOperations in the registry, so obviously it's something else, or a combination of things !?

Answer 1

You can use the Windows Update Agent API to find if a reboot is currently required to complete an update.

ISystemInformation::RebootRequired

Answer 2

I think these are a more comprehensive answers:

• http://forum.installsite.net/index.php?showtopic=18855
• http://kb.flexerasoftware.com/selfservice/viewContent.do?externalID=Q105762
• http://blogs.msdn.com/hansr/archive/2006/02/17/PatchReboot.aspx