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Sector Participants > Calendars > Planned IT Outages

Planned IT Outages

All planned IT system outages are posted as soon as they are scheduled. Participants can view outage notification details for the same day, as well as outages planned in the future.


Participants can also view information about outages that occurred in the past 60 days by selecting Archive in the table below.

Planned Outages for 28 May 2020

Outage Times Systems Description
09:30 - 09:45 EST Dispatch Service Automated dispatch instructions sent via Dispatch Service will be unavailable. The IESO will manually dispatch by phone as necessary. The Dispatch Service Web UI users may get disconnected and will need to login and verify connected after the outage.
09:30 - 09:45 EST IESO Portal Loss of access to the IESO Portal will impact the following applications:
  • Transmission Rights Auction (TRA) application will be unavailable
  • All on-line collaboration communities will be unavailable
  • Prudential Manager used to monitor and retrieve prudential information will be unavailable


EMI application used to submit bids, offers, schedules and forecasts will be unavailable. Market participants should confirm their bids and offers once the outage is completed.
09:30 - 09:45 EST Report Site Report site will be unavailable and publication of public and confidential Reports will be delayed.

Future Outages

Outage Times Systems Description
May 29, 2020
09:30 - 09:45 EST Dispatch Service Automated dispatch instructions sent via Dispatch Service will be unavailable. The IESO will manually dispatch by phone as necessary. The Dispatch Service Web UI users may get disconnected and will need to login and verify connected after the outage.
09:30 - 09:45 EST IESO Portal Loss of access to the IESO Portal will impact the following applications:
  • Transmission Rights Auction (TRA) application will be unavailable
  • All on-line collaboration communities will be unavailable
  • Prudential Manager used to monitor and retrieve prudential information will be unavailable


EMI application used to submit bids, offers, schedules and forecasts will be unavailable. Market participants should confirm their bids and offers once the outage is completed.
09:30 - 09:45 EST IESO Reports Site Report site will be unavailable and publication of public and confidential Reports will be delayed.
June 1, 2020
11:00 - 12:15 EST Sandbox Outage Coordination and Scheduling System (OCSS) - CROW Web Interface OCSS Web User Interface will be unavailable for outage submission and retrieval.OCSS Web Service will be unavailable for outage submission and retrieval.
11:00 - 12:15 EST Outage Coordination and Scheduling System (OCSS) - CROW Web Interface OCSS Web User Interface will be unavailable for outage submission and retrieval. OCSS Web Service will be unavailable for outage submission and retrieval.
09:30 - 09:45 EST IESO Portal Loss of access to the IESO Portal will impact the following applications:
  • Transmission Rights Auction (TRA) application will be unavailable
  • All on-line collaboration communities will be unavailable
  • Prudential Manager used to monitor and retrieve prudential information will be unavailable


EMI application used to submit bids, offers, schedules and forecasts will be unavailable. Market participants should confirm their bids and offers once the outage is completed.
09:30 - 09:45 EST IESO Reports Site Report site will be unavailable and publication of public and confidential Reports will be delayed.
09:30 - 09:45 EST Dispatch Service Automated dispatch instructions sent via Dispatch Service will be unavailable. The IESO will manually dispatch by phone as necessary. The Dispatch Service Web UI users may get disconnected and will need to login and verify connected after the outage.
07:00 - 07:15 EST Sandbox Dispatch Service Sandbox automated dispatch instructions sent via sandbox Dispatch Service will be unavailable.
07:00 - 07:15 EST Sandbox Portal

IESO Sandbox Portal and testing for the the following applications will be unavailable:

  • Transmission Rights Auction (TRA ) application
  • Settlements Online Forms
  • Metering (MVWeb)
  • Prudential Manager
June 2, 2020
09:00 - 10:00 EST Sandbox System and Applications Sandbox systems used for participant testing of IESO applications, including the IESO Sandbox Portal, Sandbox Reports Site, Sandbox EMI, and Sandbox Online IESO, will be unavailable.
June 10, 2020
12:15 - 16:30 EST Day-Ahead Optimization System (DAOS) The Eligible Energy Limited Resource Optimization (EELR) run of the Day-Ahead Commitment Process (DACP) DAOS will not occur:
  • EELRs will be unable to resubmit their offers for consideration in the DACP after the initial DAOS run
  • If the initial DAOS run is successful, it will be considered the Schedule of Record
12:15 - 13:15 EST Dispatch Service Automated dispatch instructions sent via Dispatch Service will be unavailable. The IESO will manually dispatch by phone as necessary. The Dispatch Service Web UI users may get disconnected and will need to login and verify connected after the outage.
13:00 - 13:10 EST IESO Reports Site The Predispatch report will not be published.