Why does Email2 not get set up for some contacts?
Neither the “Update Contacts” tool nor the HTTP Post script will create an Email2 address if the contact’s primary email address is opted out, bounced or reported spam.
This is to protect you and make 100% certain that you won’t mistakenly send an email to any of these contacts.
If you see a contact with a blank Email2 address when you’d expect it to have been created, please check the email status of their primary email address and you should be able to work out why an Email2 address wasn’t created.