Mail delivery failed: returning message to sender

[Mail Delivery System]

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  [EMAIL PROTECTED]
    SMTP error from remote mailer after RCPT TO:<[EMAIL PROTECTED]>:
    host mx4.hotmail.com [65.54.190.230]: 550 Requested action not taken:
    mailbox unavailable

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