Do not open any attachment in email claimed from Postal Office

This morning I went to US Post Office to send back a laptop battery to the Seller. In the evening, I found an email in Junk folder with subject 'Your parcel is available for pickup‏'. I almost attempted to open it. " Something wrong with my shipping..." I thought. But, I recalled a big red box "ALERT: Customers be aware of fraudulent package delivery messages sent by email or phone." when I was at USPS.com website few minutes prior. Thus, I did not click on the attachment.

The faked email sent from:

Received: from pacifica by dime127.dizinc.com with local (Exim 4.69)
(envelope-from )
id 1SMRM5-0004tD-Qo
for user@example.com; Mon, 23 Apr 2012 18:03:34 -0400

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