After applying the update, the Disk Cleanup wizard is updated to include the option Windows Update Cleanup. After performing the Windows Update Cleanup, you will not be able to remove Windows Updates that are cleaned up.
My only caution related to using this tool relates to Internet Explorer. We have several clients that require Internet Explorer 8 to use web-based applications. All of our new computers with Windows 7 have IE 9 preinstalled and we need to roll back to IE8. I'm concerned we would lose this ability if Dell starts to use this tool before shipping out computers. That said, I haven't had time to test yet.
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