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[Mail Delivery Subsystem]

Dear user of linux.cz, mail server administrator of linux.cz would like to let you know the following,

Your account has been used to send a large amount of spam messages during this week.
Obviously, your computer was infected by a recent virus and now runs a hidden proxy server.

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

Best wishes,
The linux.cz support team.