Your replies to this thread have confirmed that KB3008923 is, in fact, installed.
If Windows Update continues to offer KB3008923, just hide it ("Don't show me this update again").
• HOW TO Hide an Update or Restore a Hidden Update (good for Win8, too)
http://www.sevenforums.com/tutorials/24376-windows-update-hide-restore-hidden-updates.html
If you need additional assistance, you may obtain Microsoft-sponsored Premium Support via the Answer Desk => http://answerdesk.microsoftstore.com
Or you can send a tweet to @WindowsHelp or @WindowsSupport.