May 31: Update: Security response to the email service breach

To: Graduate students at the University of Waterloo

From: Jacinda Reitsma, Vice-President, Administration and Finance

Date: Wednesday, May 31, 2023

Subject: Update: Security response to the email service breach

Update: Security response to the email service breach

May 31, 2023

  • Online systems will experience scheduled downtime tomorrow evening at 6:30 p.m.
  • If you are already logged in to applications prior to this period, you may not experience any down time 
  • You will be required to reset your WatIAM password once the systems are back online 

On May 30, the University of Waterloo prevented an attempted ransomware-attack to our domain. Since then, we have been managing the security response to successfully limit the impact of the initial breach. Only our on-campus Microsoft Exchange email services have been affected, meaning that most of our users who work with cloud-based email have not been affected.  

As a result of this situation, we have temporarily disabled Waterloo’s WatIAM system. This restricts the ability for new user accounts to be created.

The IST team is planning for a complete authentication system shutdown tomorrow evening starting at 6:30 p.m. to restore systems, with an estimated outage time of two to six hours. As you can understand, there is a need for an urgent response to this situation. This means you will not be able to use your WatIAM credentials to sign into systems that require a login, such as Waterloo LEARN, Quest, campus and lab computers, Workday, Eduroam, and your Microsoft 365 (including email) during that period. If you stay logged in to applications during this period, you may not experience any downtime. 

Following the work, we will require you to change your WatIAM password. Please do not attempt to change your password before this shutdown as you will still be required to change it once the authentication system is restored. 

We will hold a townhall tomorrow at 2:30 p.m. to answer your questions and to share more details on the planned shutdown. Please join us then – you do not need to register. 

We know that some people are hosting or attending classes, labs, or other on-campus activities tomorrow evening. We are assessing whether there will be any impact on classes and activities. We will be working with the deans' offices to provide additional direction. Instructors will receive more information throughout the course of the day, as needed.

If you have any questions about access to your systems, please email

Jacinda Reitsma

Jacinda Reitsma
Vice-President, Administration and Finance
Office of the Vice-President, Administration and Finance

2023 communications to graduate students