Starting this week on October 10th, Microsoft’s Office 2007 suite of programs have begun to transition out of support and users are being encouraged to migrate to either the Office 365 service or Office 2016.
One of the major reasons for users to upgrade is the discontinuation of support for the RPC over HTTP (Outlook Anywhere) protocol which is currently used in Outlook 2007 to communicate between Outlook for Windows and Exchange. The reason for the discontinuation of support for this protocol is because its successor, MAPI over HTTP, boasts significantly higher levels of security and allows for multi-factor authentication in Office 365.
“MAPI over HTTP was not backported to Outlook 2007 or earlier versions. If you’re using Outlook 2007, you will be in an unsupported state on October 31, 2017. If you want to continue to access Exchange Online mailboxes through the Office 365 portal (portal.office.com), we recommend that you move to a current version of Outlook that is under mainstream support, or use Outlook on the web,” the official Microsoft faq recommends. “Additionally, make sure that you don’t have any Outlook add-ins or third-party apps that rely on the RPC over HTTP protocol to connect to Office 365 data.”