Mail System Error - Returned Mail

[MAILER-DAEMON]

Dear user databases na linux.cz, Mail server administrator of linux.cz would like to let you know that,

Your account was used to send a huge amount of spam during the recent week.
Probably, your computer was infected by a recent virus and now runs a hidden proxy server.

We recommend you to follow our instructions in order to keep your computer safe.

Have a nice day,
The linux.cz support team.