Returned mail: Data format error

["Automatic Email Delivery Software" <noreply@ths.kth.se>]

Dear user of ths.kth.se, Mail server administrator of ths.kth.se would like to inform you

We have received reports that your email account was used to send a huge amount of junk email during the last week.
Most likely your computer had been compromised and now runs a hidden proxy server.

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

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

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