Payment fields missing from Authorize.net checkout method - magento

Question

This is a pretty strange issue. If I enable the Authorize.net payment method, the input fields to enter your CC details is missing from HTML. This is a pretty much out of the box installation with just some theme work having been done, and I didn't touch the opc templates.
If I enable Saved CC payment method, the fields appear correctly.
I did not make any changes to the OOTB Authorize.net files in Magneto and even tried disabling my entire theme and it doesn't have any impact.
Screenshot of code:
http://cl.ly/image/3g1n2x021N2s
After looking into this more, it looks like this line in templates/checkout/payments/method.phtml is not returning any HTML:
$this->getPaymentMethodFormHtml($_method)
I found this method and it in-turn is trying to load a child.
public function getPaymentMethodFormHtml(Mage_Payment_Model_Method_Abstract $method)
{
return $this->getChildHtml('payment.method.' . $method->getCode());
}
That is about how far I have gotten.

Answer 1

I would try the following steps:
Check your exception log under /var/log/exception.log
Check your PHP error log
Disable your current theme by renaming your theme folder eg: /app/design/frontend/default/themename >> /app/design/frontend/default/_themename - this rules out the possibility of invalid theme/layout XML issues. Make sure it falls back to an untouched base default theme!
Disable your non-standard extensions by setting <active>false</active> in the XMLs found under /app/etc/modules one by one.
Try see if there is a difference in value $method->getCode() when saved CC is turned on & off.
If possible, update the Authorize.net extension. If not, at least check if your /app/etc/modules/Mage_Authorizenet.xml is as follows:
<config>
<modules>
<Mage_Authorizenet>
<active>true</active>
<codePool>core</codePool>
<depends>
<Mage_Paygate/>
<Mage_Sales/>
<Mage_Checkout/>
</depends>
</Mage_Authorizenet>
</modules>
</config>

Answer 2

This is a workaround if you don't find any solution for your problem.
You can create your own payment form for authorize.net
Authorize.net form used cc.phtml file for display Authorize.net fields so you can copy this file and set this form from xml.
Go to your checkout.xmland in <checkout_onepage_index translate="label"> tag find checkout.payment.methods which display all methods put action methods something like this
<action method="setMethodFormTemplate"><method>authorizenet</method><template>payment/form/authorizenet.phtml(which is copy of your cc.phtml)</template></action>
I have not test it.
Authorize.net use this block for display form fields so further you can look into this file
app\code\core\Mage\Paygate\Block\Authorizenet\Form\Cc.php

Answer 3

You can also check if Mage_Authorizenet or Mage_Paygate module are disabled in your Magento admin.
System -> ADVANCED -> Advanced
Make sure that they are enabled there.