Worm Attack - W32.Mimail.A@mm

I received > 10 emails from my User Group email account today, all of them containing an attachment - message.zip, and all of them are send from the same admin account of my .NET User Group!

That's obviously odd as I 'm sure there's NO email address with the name of “admin” (I'm one of the domain and email administrators for my User Group domain name) AND all of the emails with the same message body and attachment:

I would like to inform you about important information regarding your email address. This email address will be expiring. Please read attachment for details.

Best regards,
Administrator

Attachment: message.zip

Therefore, I search and find that a worm named “W32.Mimail.A@mm” discovered on August 01, 2003. Now, I made an announcement in my User Group's Forum and notify all members. Just in case any of the members got infected by this virus, I'm worrying that it will damage the reputation and become the responsibility and fault of my User Group then...