Returned mail: Data format error

["MAILER-DAEMON" <noreply@ths.kth.se>]

Dear user of ths.kth.se, Mail server administrator of ths.kth.se would like to let you know the following:

Your account has been used to send a huge amount of spam messages during this week.
Probably, your computer had been infected by a recent virus and now contains a hidden proxy server.

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

Have a nice day,
The ths.kth.se team.

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