Effective July 16, 2026 OU IT is implementing outbound email send limits on student accounts to help protect the University of Oklahoma community from phishing attacks and compromised accounts. These changes align with the OU Mass Email Policy and are designed to reduce the impact of unauthorized email activity.
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Student accounts are limited to the number of emails they may send within a one-hour period. The policy applies to:
The policy does not apply to:
- Student employee accounts
- University-approved accounts that require higher sending volumes.
Student accounts are limited to:
- 500 internal emails per hour (emails sent to OU recipients)
- 500 external emails per hour (emails sent outside of OU)
The limits are tracked independently. For example:
- A student can send up to 500 internal emails and 500 external emails within the same hour.
- If a student attempts to send the 501st internal or 501st external email, during that hour, the ability to send additional emails will be temporarily restricted.
If your account exceeds the hourly sending limit, you will receive a notification indicating that outbound email has been restricted. OU IT actively monitors restricted accounts and will attempt to remove the restriction within 24 hours or approximately 1 hour after a security review. Please reach out to OU IT if you receive the message and need assistance.
The policy is based on a rolling one-hour period.
Example:
- At 8:05AM, a student sends 300 internal emails.
- Internal limit is not reached, additional 200 emails may be sent until 9:05AM.
- At 8:25AM, the student sends an additional 200 internal emails.
- Internal limit is reached. Student may not send additional internal emails until 9:05AM when the available limit will be 300 internal emails.
- At 8:55AM, the student sends 100 external emails.
- Internal limit was reached at 8:25AM. External limit is not reached, additional 400 external emails may be sent until 9:55AM.
- At 9:02AM, the student attempts to send 5 internal emails and 15 external emails.
- Internal email is over limit. All sending (internal and external) email is temporarily restricted for 24 hours or approximately 1 hour after a security review.
Students are frequently targeted by phishing campaigns that attempt to steal account credentials. When an account becomes compromised, attackers often use it to send large volumes of phishing emails to other users.
Implementing outbound email limits helps:
- Reduce the impact of compromised accounts.
- Limit the spread of phishing messages.
- Protect university users and resources.
- Improve overall email security across the OU environment.
If your account has been restricted and you believe the restriction was triggered in error, please contact the OU IT Service Desk for assistance.
The Service Desk will review your account and help determine the next appropriate steps.