title: "This certificate is not yet valid" error on Mac
body: <p>I have all my mac app developer certificates valid and expiring in 2019. After code signing the application and the installer pack, users would get a this: "app name was signed with a certificate that has expired. If you acquired this message recently, it may not be authentic. Do you want to continue".</p>
  
  <p>Upon clicking show certificate, it says that the certificate expires in 2019 and below that "This certificate is not yet valid."</p>
  
  <p>I found very little information from others with this error. And I have tried setting the date and time perfectly and it still didn't work.</p>