A revision was made to the WSUS offering for Windows 7 / Window Server 2008 R2 Service Pack 1 (SP1) on 5/24 to address known installation issues. We are aware that this latest revision is incorrectly reporting as "Not Installed" for machines that have already installed the previous revision of the SP1 update. Also, if this revision is approved for installation, it will reoffer to machines that have already installed the previous revision of the SP1 update. Specifically
UPDATE: This issue has been corrected with a revision released Tuesday, 5/31 at 10:00 a.m. Pacific Time.