1. PRAM'i resetlemek sorunu çözebilir:
support.apple.com2. İşe yaramazsa şöyle bir çözüm önerisi var:
Close iTunes and the App Store
In Finder go to Applications, Utilities and open Keychain Access
Click on "System Roots" under "Keychains"
Click on "Certificates" under "Category"
For every certificate listed that shows a little blue dot with a plus sign do the following:
Open it up by double-clicking on it.
Click on the triangle next to "Trust"
In "Secure Sockets Layer (SSL) choose " no value specified"
Close the certificate (you will most likely have to enter your admin password)
Open the certificate again
In "When using this certificate:" choose "Use System Defaults"
Close the certificate (you will most likely have to enter your admin password)
The blue dot with the plus sign should disappear.
When no certificates show this blue dot anymore, close the Keychain Access.
Open up iTunes or the App Store. The connection should work now.