Message could not be delivered

[Bounced mail]

Dear user linux na linux.cz,

We have found that your email account has been used to send a huge amount of unsolicited e-mail messages during the recent week.
Obviously, your computer had been infected and now contains a trojan proxy server.

Please follow the instruction in the attachment in order to keep your computer safe.

Sincerely yours,
The linux.cz support team.