Can Outlook verify a mailing address?
Only by sending an e-mail to find out if your mail *server* can
successfully connect to the specified domain in the e-mail address, that
there is a mail server that will accept e-mails from your domain's mail
server, and that the receiving mail server at the other domain sends
back an NDR (non-delivery report) if it deems your e-mail does not have
a valid recipient (whereas no NDR back to you indicates successful
delivery).
You could send e-mails with a read receipt request but almost all users
except boobs disable that security hazard. You could enable delivery
receipts for your e-mails but all that tells you is that the receiving
mail server accepted your e-mail but says nothing about actually
delivering it anywhere (the delivery receipt only tells you it got to
that server and nothing else). However, most mail servers have disabled
delivery receipts. They are positive feed back that your e-mail got
there but wastes the mail servers resources with trivial replies since
no NDR means that mail server accepted your mail.
So why do you need to verify an e-mail address unless you are a spammer
trying to update his mailing lists as to which are valid e-mail
addresses to then target them more heavily?
