The March 2012 Optional Updates are now available on the ECE site for Windows Embedded POSReady 7 OEMs. This month’s .img contains just one update, namely
KB2685747 – Fix for the issue where Keyboard Filter doesn't block Ctrl-Alt-Del when the user unplugs the USB keyboard and plugs it into another port.
If you have questions on accessing the ECE, please email MS Mobile & Embedded Communications Feedback & Support, ECE@microsoft.com.
Volume License customers can get the update from the Download Center.