title: Understanding Microsoft Hotfix numbers
body: <p>I got the Microsoft Security Bulletin MS16-008:<br>
  <a href="https://technet.microsoft.com/library/security/ms16-008" rel="nofollow">https://technet.microsoft.com/library/security/ms16-008</a><br>
  The title names a security update "3124605", so I expected find the hotfix KB3124605 on my system (Windows 8.1), but it's not installed.<br>
  The bulletin also refer to the hotfix KB3121212, which actually is installed on my system. </p>
  
  <p>Why are there two different KB numbers for the same thing?</p>
  
  <p><a href="https://support.microsoft.com/kb/3124605" rel="nofollow">https://support.microsoft.com/kb/3124605</a><br>
  <a href="https://support.microsoft.com/kb/3121212" rel="nofollow">https://support.microsoft.com/kb/3121212</a> </p>