Practical playbook to discover, categorise and migrate EWS-based integrations in Exchange Online before the October 2026 phased disablement and the 2027 full shutdown.

SMTP AUTH Basic Authentication in Exchange Online is being phased out. This guide shows how to find every sender still using it, choose the right migration path, and move to OAuth, SMTP Relay, HVE, or Graph API before it breaks production.

Exchange Web Services (EWS) is being retired in Exchange Online. Many organizations still rely on legacy integrations that could silently break. This article explains the outage risks and provides a practical migration strategy to Microsoft Graph.