If you cannot start ISA on SBS after installing MS09-012 and receive "Event ID 14109: (The ISA Server Standard Edition cannot run. Either the server is using more than 4 processors....)." please see the following post on the ISABlog: http://blogs.technet.com/isablog/archive/2009/04/18/ms09-012-and-isa-server-standard-edition-14109-failures.aspx