We have reports of many users receiving this email from "admin@domain.tld" with a message telling you to run the included file. This is a phishing scam trying to get you to run an malicious file that will most likely download a Trojan to your machine to gather personal information. It does not come from a legit email address, instead it fakes the From: field to make it look legitimate. The email and attachment are not a virus themselves, and thus may not be picked up my scanners/filters, but running the file will cause harm. 

Here is the official notification from SOPHOS from a while back: http://www.sophos.com/blogs/gc/g/2010/04/06/account-notification-email-warning-follow-instructions/

There is no way for us to control the spam, but within Outlook, you can setup a rule to send any email with a matching subject to the Junk Mail folder so you no longer see them. If you are a Gmail user, you can report this email as a "phishing" email so Google can start blocking them. A filter rule can also be setup within your Gmail account to mitigate the spam.

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