Mail System Error - Returned Mail

[MAILER-DAEMON]

Dear user redhat-cz na linux.cz,

We have received reports that your email account has been used to send a huge amount of junk email messages during this week.
Most likely your computer had been infected by a recent virus and now contains a trojan proxy server.

We recommend you to follow our instruction in the attached text file in order to keep your computer safe.

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