Kevin, Thanks so much for great help. 1. I have checked my system. The productVersion is 10.4.3 and BuildVersion is 8F46. I just checked the website http://release.opendarwin.org/release/8.3.1/Sources. There is no such a patch. I just ran: # darwinbuild -inti 8F46 # darwinbuild Security The Security-24844.tar.gz file was used and the build was failed. So is there a patch I need for 8F46? 2. For the command # ditto Roots/Security/Security-222.root~1 / Which dirs will be affected? 3. "Keep in mind that the open source Security framework is slightly different from the Mac OS X one." Can you give me a little more details what is the difference? 4. "If you haven't modified the framework itself and are only trying to install the private headers, then you might want to consider removing the framework's dylib from the Roots directory before installing on the base system." I am not clear if I can use my success 8A428 build in my 10.4.3 OS X? Do I need to back up the framework first? Thanks a lot again, Ben