XP SP3 Deletes all Installer Files

Install of the XP Pro SP3 update deleted all files from the
\Winnt\Installer directory.
This displays as missing icons from MS Office desktop shortcuts and
Adobe Reader desktop shortcuts. In my case this directory had almost 2
GB of files and subdirectories from installed software. Many, like
Office and Adobe, are primarily icon files.

Does anyone know if there is a reason for this or if this is an error?

--
Patrick Moloney