I'm having a similar issue without the # symbol (email pasted below). Can you take a look and see if there are any invalid characters in my test receipt?
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Subject: Merchant Email Receipt
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========= SECURITY STATEMENT ==========
It is not recommended that you ship product(s) or otherwise grant services relying solely upon this e-mail receipt.
========= GENERAL INFORMATION =========
Merchant : Merchant Name (366278)
Date/Time : 18-Jul-2013 10:06:04 PDT
========= ORDER INFORMATION =========
Invoice :
Description : APP Application Fee
Amount : 125.00 (USD)
Payment Method : American Express
Type : Authorization and Capture
============== RESULTS ==============
Response : This transaction has been approved.
Authorization Code : 3C0YU9
Transaction ID : 2195833092
Address Verification : Street Address: Match -- First 5 Digits of Zip: Match
==== CUSTOMER BILLING INFORMATION ===
Customer ID : 29796
First Name : Test
Last Name : User
Company : Child & Family Guidance Center Address : 6851 Lennox Avenue City : Van Nuys State/Province : CA Zip/Postal Code : 91405 Country : N/A Phone : 818-887-0967 Fax : N/A E-Mail : test@test.com
==== CUSTOMER SHIPPING INFORMATION ===
First Name : Test
Last Name : User
Company : Child & Family Guidance Center Address : 6851 Lennox Avenue City : Van Nuys State/Province : CA Zip/Postal Code : 91405 Country : N/A
======= ADDITIONAL INFORMATION ======
Tax : 0.00
Duty : 0.00
Freight : 0.00
Tax Exempt : No
PO Number : N/A