It's had a good run but time is running out on POP. Legacy POP e-mail (Post Office Protocol) services where Outlook downloads mail are being replaced by automatically synchronizing, secure, reliable, and feature rich Office 365 hosted Exchange email. Instant synchronization of messages, calendar entries, contacts and tasks between all devices has become the standard. Users need everything on their desktop Outlook to be mirrored on mobile devices, laptops, and on webmail.