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:

  vcreklama na seznam.cz
    SMTP error from remote mail server after RCPT TO:<vcreklama na seznam.cz>:
    host mx1.seznam.cz [77.75.78.42]: 550 5.1.1 Sorry, no mailbox here by that name.
  sadsdsd na seznam.cz
    SMTP error from remote mail server after RCPT TO:<sadsdsd na seznam.cz>:
    host mx1.seznam.cz [77.75.78.42]: 550 5.1.1 Sorry, no mailbox here by that name.
  hrasek.1998 na email.cz
    SMTP error from remote mail server after RCPT TO:<hrasek.1998 na email.cz>:
    host mx1.seznam.cz [77.75.78.42]: 550 5.1.1 Sorry, no mailbox here by that name.
  dzyssis na seznam.cz
    SMTP error from remote mail server after RCPT TO:<dzyssis na seznam.cz>:
    host mx1.seznam.cz [77.75.78.42]: 550 5.1.1 Sorry, no mailbox here by that name.
  leblanc26 na centrum.cz
    SMTP error from remote mail server after RCPT TO:<leblanc26 na centrum.cz>:
    host cax.virusfree.cz [5.180.49.35]: 554 5.7.1 <leblanc26 na centrum.cz>:
    Recipient address rejected: Access denied, user does not exist