Unexpected error when sending group e-mail

[Prefontaine]

I have used Outlook for years to send a daily e-mail message to a group of about 35. About two weeks ago, I started getting the message "an unexpected error has occured" whenever I attempt to send the message. I can continue to send and receive all my other messages, just not the large group e-mail. I can also cut and paste the message, switch to Outlook Express and use it with no difficulty.

Just to see if it helped, I deleted my entire Office XP suite and re-installed, but no success.

Any ideas?

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