Every day, at least twice, Microsoft Automatic Updates announces it wants to download Security Update for Microsoft XML Core Services 4.0 Service Pack 2 (KB936181). I Click the Download button. It starts the install, I even watch the progress bar. When it is through it announces the installation is complete. But sometime later in the day, it goes through the same process again. Can anyone shed some light?
Those known issues can happen sometimes with some of the automatic updates and manually downloading and installing the update is typically the workaround as detailed in that Microsoft KB article suggests:
To work around this problem, manually install the security update from the Microsoft Download Center, and then click Ignore when the error message is displayed. To confirm that the installation was successful, verify that the Msxml4.dll file in %systemroot%\System32 is version 4.20.9848.0.