There are a few new viruses going around and they "spoof" the email of a sender that you may know, but it is not necessarily from them, and they are probably unaware that the virus is "spoofing" their email address.
We have received several of these today.
Be very cautious opening attachments if you don't know what they are.  Some of the SUBJECTS, BODY contents, and ATTACHMENTS of the viruses are as follows:
SUBJECT: (Varies, such as)
Error 
Status 
Server Report 
Mail Transaction Failed 
Mail Delivery System 
hello 
hi 
BODY:  (Varies, such as) 
The message cannot be represented in 7-bit ASCII encoding and has been sent as a binary attachment. 
The message contains Unicode characters and has been sent as a binary attachment. 
Mail transaction failed. Partial message is available. 
ATTACHMENT: (varies [.bat, .exe, .pif, .cmd, .scr] - often arrives in a ZIP archive) (22,528 bytes)
EXAMPLES (common names, but can be random) 
doc.bat 
document.zip 
message.zip 
readme.zip 
text.pif 
hello.cmd 
body.scr 
test.htm.pif 
data.txt.exe 
file.scr 
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