You receive the"0x800CCC69 SMTP_550_MAILBOX_NOT_FOUND" error message or the “503 Sender already specified” error message when you try to send an e-mail message in Outlook Express or in Outlook on a computer that is running Windows XP Home Edition
When you use Microsoft Outlook or Microsoft Outlook Express on a computer that is running Microsoft Windows XP Home Edition to send a new e-mail message, you may experience the following symptoms:
In Outlook, you may receive the following error message:
Unable to deliver the message due to a communication failure ……………………… 503 Sender already specified.
In Outlook Express, you may receive the following error message:
You may contact Zero-Knowledge Systems Inc. if you require help in configuring t...
You may contact Zero-Knowledge Systems Inc. if you require help in configuring the firewall in Freedom program so that it is compatible with Outlook and Outlook Express.
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