NOTICE DATE:  May 27, 2009

NOTICE TYPE:  M-A052709-01 INITIAL: Maintenance Outage – Retail/Wholesale

SHORT DESCRIPTION:  Scheduled Maintenance Outage

INTENDED AUDIENCE:  All Market Participants

DAY AFFECTED:  Sunday, June 7, 2009 from 6:00 AM through 9:00 PM

LONG DESCRIPTION:  ERCOT has scheduled a maintenance outage for Sunday, June 7, 2009 from 6:00 AM through 9:00 PM.

ADDITIONAL INFORMATION:  During the outage the following functions will be affected:

• Market Participants utilizing NAESB to send/receive transactions to/from ERCOT will NOT be able to send/receive transactions to/from ERCOT during the outage.   This includes all retail transactions.
• 867 transactions will NOT be forwarded during the outage.
• 997 Functional Acknowledgements will NOT be sent during the outage.
• Components of the TML and Commercial API will NOT be available including:

• Find ESI ID
• Find Transaction
• Submit Transactions
• USA Functionalities
• Report Explorer, including

• Reports
• Extracts
• Invoices
• Settlement Statements

• Extract Scheduler
• Web Services Data Requests 

• ERCOT Internet Services will NOT be available, including but not limited to:

• ERCOT.com – www.ercot.com
• MarkeTrak - https://marketrak.ercot.com:8443/tmtrack.dll?
• TCR - https://tcr.ercot.com
• Texas Renewables – www.texasrenewables.com

MOS, Scheduling API, MOSTML, MOSPUBLIC, and Outage Scheduler will not be affected as there will be a DNS failover from Taylor to Austin.

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].

If you are receiving e-mail from an ERCOT distribution list that you no longer wish to receive, please follow this link in order to unsubscribe from this list: http://lists.ercot.com.

JR/DP/DH