Microsoft began retiring Exchange Web Services (EWS) in Exchange Online on October 1, 2026. EWS is an older technology used by some email and calendar applications and is being replaced by more secure, modern connection methods.

As Microsoft rolls out this change over the next six months, people using older devices, unsupported operating systems, or outdated email and calendar applications may experience problems connecting to Cornell email and calendar services.

Don't Wait Until Something Stops Working

To reduce the risk of service disruptions:

• Install available updates for your devices and operating systems.
• Update your email and calendar applications to current, supported versions.
• Use a Microsoft-supported Outlook client whenever possible.
• Replace devices that can no longer run supported software.

Email Notification for Impacted EWS Application Use

When available reporting tools indicate to Information Technology at Cornell that a community member’s application is currently connecting through EWS, email notifications are distributed to that person’s campus email address. However, not all affected devices and applications can be identified with existing resources. If you use older hardware or software, do not assume you are unaffected simply because you have not received an email notification.

Learn More, Get Help

Review the Prepare for EWS Retirement webpage for information about supported email clients, potentially affected devices, and recommended actions.

Need help? Contact the Information Technology Service Desk.