Once an account is completely setup on Proofpoint Essentials User Interface according to the getting started guide found, the partners/customers should wait until the top of the 30 minutes for the changes to update across Proofpoint Essentials Network before testing the service. If you need a copy of the Getting Started Guide, please contact Support or your Reseller.

Partners/Customers should ensure that they have provided all the required information and the following have been configured (Any changes made will take effect at the top of the 30minutes).

• Correct SMTP destination IP address(es)/hostname(s) entered
• Firewall lockdown for Proofpoint IP ranges.
• MX records updated.

If emails are not being delivered from one particular domain 

If you are not receiving email from a certain domain, it could be due to one of the reasons below

• The sender is on one or more of Proofpoint's email blacklists. 
• There is an issue with the senders SMTP server
• Emails might have been detected as spam and should be visible in the users quarantine.