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 Edi...

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:
  
  error: 0x800CCC69 SMTP_550_MAILBOX_NOT_FOUND

This issue may occur if the firewall settings in the Freedom program from Zero-Knowledge Systems Inc. are not configured correctly on your computer.

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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