Today’s blog is going to cover some issues regarding the installation of MS12-034 (2686509).  When installing this update you may encounter the following error message:

Setup cannot continue because one or more prerequisites required to install KB2686509 failed (0x8007F0F4)

The existence of %windir%\FaultyKeyboard.log indicates that we found a keyboard layout registered on the computer but the files do not exist in the %Windir%\System32 folder. 

If you encounter the error and a FaultyKeyboard.log is not created there is some other possible causes and solutions.  The following KB article is being updated on regular basis to list out possible solutions so you should always check it for updated information

MS12-034: Description of the security update for CVE-2012-0181 in Windows XP and Windows Server 2003: May 8, 2012

Thanks and I hope this helps
Scott McArthur
Senior Support Escalation Engineer