I cannot synch 10 most recent iPhone purchased applications with iTunes. The 10 also don't appear in Apple Store history of purchases. I get the error that my computer is not authorized (and it is). This problem started after upgrading iMac from Tiger to Snow Leopard. I have tried all solutions on forum as well as suggestions at apple.com support with no success. Running latest Snow Leopard OS, latest iTunes and latest firmware on iPhone 4.