NOTICE DATE: March 6, 2012

NOTICE TYPE: M-B030612-01 Outage – Retail/Wholesale

INTENDED AUDIENCE: All Market Participants

DAY AFFECTED: March 6, 2012 from 11:16 to 12:09

DESCRIPTION: Between 10:35 and 11:16, web services became partially unavailable, and market participants using these services saw a degraded response to market submissions and data retrievals. At 11:16, web services became completely unresponsive, preventing submissions and data retrievals.

Day Ahead Market (DAM) was manually closed at 11:45.

At 12:09, web services were restored, and are fully functional.

ERCOT is currently researching the root cause.

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 e-mail at [log in to unmask].

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