NOTICE DATE: April 6, 2022

NOTICE TYPE: M-A021722-05 Release

SHORT DESCRIPTION: Reminder - ERCOT Ending Support of Internet Explorer (IE) on Market Management System User Interface (MMSUI) and Outage Scheduler (OSUI) applications

INTENDED AUDIENCE: Qualified Scheduling Entities (QSEs) and Transmission Service Providers (TSPs)

EFFECTIVE DATE: April 07, 2022

LONG DESCRIPTION: Microsoft plans to end support of all IE browsers in June 2022. ERCOT is in the process of ensuring all Market-facing applications support Chromium browser platforms (Microsoft Edge and Google Chrome). In accordance with this plan, ERCOT will release the Chromium-based version of MMSUI and OSUI on April 07, 2022. As of April 07, 2022, only Microsoft Edge and Google Chrome browsers will be supported by the MMSUI and OSUI applications. It should be noted that users will be able to open only one MMSUI or OSUI browser session at a time in Google Chrome or Microsoft Edge.

ACTION REQUIRED: As of April 07, 2022 only use Google Chrome or Microsoft Edge with ERCOT MMSUI and OSUI applications.

ADDITIONAL INFORMATION: ERCOT designates the supported browser for each of its applications on the Applications page of ERCOT.com. Click the purple Help button at the bottom right of the page to view this information.

CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at [log in to unmask].

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