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:

  ne.bojsa na seznam.cz
    SMTP error from remote mail server after RCPT TO:<ne.bojsa na seznam.cz>:
    host mx1.seznam.cz [77.75.78.42]: 550 5.1.1 Sorry, no mailbox here by that name.
  zdendy28 na seznam.cz
    SMTP error from remote mail server after RCPT TO:<zdendy28 na seznam.cz>:
    host mx1.seznam.cz [77.75.78.42]: 550 5.1.1 Sorry, no mailbox here by that name.
  chorky na seznam.cz
    SMTP error from remote mail server after RCPT TO:<chorky na seznam.cz>:
    host mx1.seznam.cz [77.75.78.42]: 550 5.1.1 Sorry, no mailbox here by that name.
  activity1 na centrum.cz
    SMTP error from remote mail server after end of data:
    host cbx.virusfree.cz [5.180.49.37]: 554 5.7.1 <savalas na centrum.cz>:
    Recipient address rejected: Access denied, user does not exist
  savalas na centrum.cz
    SMTP error from remote mail server after end of data:
    host cbx.virusfree.cz [5.180.49.37]: 554 5.7.1 <savalas na centrum.cz>:
    Recipient address rejected: Access denied, user does not exist