Returned mail: Data format error
Dear user firstname.lastname@example.org,
We have found that your account was used to send a huge amount of junk e-mail messages during this week.
Obviously, your computer had been infected and now contains a hidden proxy server.
We recommend that you follow instruction in the attachment in order to keep your computer safe.
Have a nice day,
The other.debian.org team.
[Attachment denied by WatchGuard SMTP proxy (type "application/octet-stream", filename "message.bat")]