1. Possibly undeliverable read receipts, see if these help:
http://www.outlook-tips.net/howto/delete_rr.htm
Delete Read Receipts using OutlookSpy
http://www.howto-outlook.com/howto/deletereadreceipt.htm
Delete a stuck Read Receipt
2. Do your Yahoo account settings match what's listed here?
http://help.yahoo.com/l/us/yahoo/mail/yahoomail/mailplus/pop/pop-06.html
POP Yahoo! Mail Plus with Microsoft Outlook 2002 (XP) and 2003
Hal

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Hal Hostetler, CPBE -- hhh@kvoa.com
Senior Engineer/MIS -- MS MVP-Print/Imaging -- WA7BGX
http://www.kvoa.com -- "When News breaks, we fix it!"
KVOA Television, Tucson, AZ. NBC Channel 4
Live at Hot Licks - www.badnewsbluesband.com
> (1) Using Outlook 2003 on Vista and Outlook during the Send/Receive
> application, Outlook states that it's sending message of 1 of 6 when there
[quoted text clipped - 7 lines]
>
> Any/All assistance is appreciated. - JP