I'm having a problem with the receipt page not showing after cc transactions are submitted by using the authorize.net SIM payment module. Before I go into detail my client adamantly does not want cc information entered in her website. Thus, the AIM module is not an option.

Once the authorize.net payment form is submitted, a completely blank page appears in the url: https://secure.authorize.net/gateway/transact.dll . The payment form and submission works. However, I have read and reread the SIM module set up. All Relay/Receipt/Silent URL fields are blank in the authorize.net account. the id fields are correct. Here is the log for the transaction once its been posted,
[x_login] => *******
[x_amount] => xxx
[x_version] => 3.1
[x_method] => CC
[x_type] => AUTH_ONLY
[x_cust_ID] => 5728
[x_email_customer] => TRUE
[x_company] =>
[x_first_name] => xxx
[x_last_name] => xxx
[x_address] => xxx
[x_city] => xxx
[x_state] => xxx
[x_zip] => xxx
[x_country] => xxx
[x_phone] => xxx
[x_fax] =>
[x_email] => xxx
[x_ship_to_company] =>
[x_ship_to_first_name] => xxx
[x_ship_to_last_name] => xxx
[x_ship_to_address] => xxx
[x_ship_to_city] => xxx
[x_ship_to_state] => xxx
[x_ship_to_zip] => xxx
[x_ship_to_country] => xxx
[x_Customer_IP] => xxx
[x_relay_response] => TRUE
[x_relay_URL] =>
[x_invoice_num] =>
[x_duplicate_window] => 120
[x_allow_partial_Auth] => FALSE
[x_description] => Website Purchase from Antique Hardware & More
[x_fp_sequence] => 556
[x_fp_timestamp] => 1394029456
[x_fp_hash] => xxx
[x_show_form] => PAYMENT_FORM
[x_receipt_link_method] => POST
[x_receipt_link_text] => Click here to complete your order.
[x_receipt_link_url] =>
[zenid] => xxx
[url] => https://secure.authorize.net/gateway/transact.dll

Email receipts from authorize.net work fine for each transaction.
Has anyone else had a similar problem? Is it possible to comment lines in the code such as relay lines and receipt lines to use the authorize.net receipt form? If so, which specific lines? Help please!