Verify Email Address Using Outlook Global Address List In Python

I am trying to verify if internal email address is valid based upon Outlook Global Address List and found out this approach here The code I am using is as follows: outlook = win32c

Solution 1:

If your string looks like an SMTP address, Outlook will resolve it as a one-off SMTP address. The prompt "We won't be able to deliver this message because email address is no longer valid" comes from the EWS API (MailTips command).

You can check if the returned Recipient.AddressEntry.Type == "EX" for a GAL entry. If you pass any other SMTP address not present in GAL, the address type will "SMTP".