Update as of Jan. 7 at 10:45 a.m. — Microsoft has indefinitely canceled the planned external recipient email change. No action is required from units. Please continue using existing processes or third‑party tools for large‑scale communications. Learn more about this Microsoft change.
Please see the following scheduled Microsoft change:
Date: October 2026 (An exact implementation date for WSU’s Microsoft environment is unavailable.)
The following work is being completed: Microsoft is implementing a limit to the maximum number of external recipients a user can email from an Exchange Online mailbox within a rolling 24-hour period.
All affected groups: Users who regularly send emails to large external recipient audiences via Exchange Online mailboxes
All affected processes:
- Microsoft’s External Recipient Rate (ERR) limit sets a maximum of 2,000 external recipients per mailbox per 24 hours. External recipients are email addresses that deliver to any destination outside the WSU Exchange Online environment.
- If a mailbox exceeds the External Recipient Rate (ERR) limit, its ability to send email to external recipients may be restricted for up to 24 hours.
- This change will reduce WSU’s current tenant limit from 5,000 to 2,000 external recipients.
Duration of impact: This is a permanent, Microsoft-driven change.
Necessary follow-up steps:
- Impacted areas are encouraged to review and implement third-party email services for frequent bulk outreach that exceeds 2,000 external recipients.
- Review FAQs on Microsoft’s ERR limit.
Questions? Please contact Crimson Service Desk at crimsonservicedesk@wsu.edu or 509-335-4357.