NOTICE DATE: March 11, 2011

NOTICE TYPE: W-A021611-03 Release – Wholesale

SHORT DESCRIPTION: Implementation of defect repairs – updated list

INTENDED AUDIENCE: ERCOT Market Participants

DAYS AFFECTED: February 23 – March 31, 2011

LONG DESCRIPTION: ERCOT has been migrating corrections to a number of market-facing defects. ERCOT began implementing these corrections in the production environment on February 23, 2011, and will continue through March 31, 2011. The attached spreadsheet has been updated to reflect which corrections are complete and to provide an estimate of the release date for each remaining defect in this list.

ADDITIONAL INFORMATION: Intermittent system availability may be incurred due to implementation of the attached defects. The systems include, but are not limited to:

· Report publishing to the ERCOT Market Information System (MIS)

· Downloading of extracts and reports from TML Report Explorer, PI API, MIS and External Web Services (EWS)

· Market Participant notifications

· Applications impacted include: CRR, MMS UI, OS UI and MPIM

Subsequent Notices will be sent to announce any market facing outages as release dates approach.

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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