I have no idea who ACH are. You should NEVER open a .zip attachment from someone unless you know exactly where it came from. This one was removed by my anti-virus software as it contained a trojan.
ACH Payment Canceled
The ACH transaction,
recently initiated from your checking account (by you or any other person),
was canceled by the other financial institution.
Transaction ID: 3983204
Reason for rejection: See details in the attachment
Transaction Report: report_082011-65.pdf.ZIP (ZIP archive, Adobe PDF)
13450 Sunrise Valley Drive, Suite 100 Herndon, VA 20171 (703)561-1100 2011
NACHA – The Electronic Payment Association