Site rejects orders because "the e-mail cannot be sent". How do I view the site error logs?

[KitiKatica]

Hi guys.

Sometime in the last few weeks, our website (Magento CE 1.7) would randomly refuse to process orders from random customers, though none of us can make sense of why. Here is a small excerpt from the error message that is e-mailed to us and the customer:

• Reason: The email could not be sent.
• Checkout Type: onepage

The customer's e-mail is valid, so that is not the issue. We run our credit cards through Authorize.net, and when we spoke to them they found no problems on their side. It seems to be an issue within Magento itself. When the customer calls us about the problem, we process their orders over the phone with no issue.

My questions for everyone here are:

1. Have you ever experienced this problem?

2. How do I view the Magento error logs? I have heard that there's some kind of console I can view them in, but I can't remember where that is or how to run it.

I know that logs are turned on in System > Advanced > Developer > Log Settings and that's already been set up. I can find the physical files in our FTP, but when I download them they can only be viewed in Notepad and appear as a giant block of text with no real formatting. I need to be able to make sense of what I am seeing without spending an excessive amount of time adding spaces and line breaks on my own.

Nevermind, some of the logs are posted below. 

[KitiKatica]

Oh, I need to add one more comment.

I managed to get ahold of a customer who ran into this error, and as we were on the phone I actually tried to place the same order through the admin panel into her account. It gave me a vague error message about not being able to process the order, even though I was doing it as the site admin.

What gives?

I've attached a small chunk of the error logs pertaining to ONE instance of this error below.

2015-10-16T02:09:09+00:00 ERR (3):

exception 'Zend_Mail_Transport_Exception' with message 'Missing To header' in /chroot/home/removed/removed.com/html/includes/src/Zend_Mail_Transport_Sendmail.php:182

Stack trace:

#0 /chroot/home/removed/removed.com/html/includes/src/Zend_Mail_Transport_Abstract.php(337): Zend_Mail_Transport_Sendmail->_prepareHeaders(Array)

#1 /chroot/home/removed/removed.com/html/includes/src/Zend_Mail.php(1194): Zend_Mail_Transport_Abstract->send(Object(Zend_Mail))

#2 /chroot/home/removed/removed.com/html/includes/src/Mage_Core_Model_Email_Template.php(454): Zend_Mail->send()

#3 /chroot/home/removed/removed.com/html/includes/src/Mage_Core_Model_Email_Template.php(506): Mage_Core_Model_Email_Template->send(NULL, NULL, Array)

#4 /chroot/home/removed/removed.com/html/includes/src/MageParts_Base_Helper_Mail.php(98): Mage_Core_Model_Email_Template->sendTransactional('confirmcustomer...', 'general', NULL, NULL, Array)

#5 /chroot/home/removed/removed.com/html/includes/src/MageParts_Confirmcustomer_Helper_Mail.php(87): MageParts_Base_Helper_Mail->send(Array, 'confirmcustomer...', 'general', Array, '1')

#6 /chroot/home/removed/removed.com/html/includes/src/MageParts_Confirmcustomer_Model_Observer.php(105): MageParts_Confirmcustomer_Helper_Mail->submitNotifications(Object(Mage_Customer_Model_Customer), true)

#7 /chroot/home/removed/removed.com/html/includes/src/__default.php(21067): MageParts_Confirmcustomer_Model_Observer->autoApproveCustomerAccount(Object(Varien_Event_Observer))

#8 /chroot/home/removed/removed.com/html/includes/src/__default.php(21046): Mage_Core_Model_App->_callObserverMethod(Object(MageParts_Confirmcustomer_Model_Observer), 'autoApproveCust...', Object(Varien_Event_Observer))

#9 /chroot/home/removed/removed.com/html/app/Mage.php(447): Mage_Core_Model_App->dispatchEvent('customer_save_b...', Array)

#10 /chroot/home/removed/removed.com/html/includes/src/__default.php(5712): Mage::dispatchEvent('customer_save_b...', Array)

#11 /chroot/home/removed/removed.com/html/includes/src/Mage_Customer_Model_Customer.php(194): Mage_Core_Model_Abstract->_beforeSave()

#12 /chroot/home/removed/removed.com/html/includes/src/__default.php(5637): Mage_Customer_Model_Customer->_beforeSave()

#13 /chroot/home/removed/removed.com/html/includes/src/Mage_Core_Model_Resource_Transaction.php(151): Mage_Core_Model_Abstract->save()

#14 /chroot/home/removed/removed.com/html/includes/src/Mage_Sales_Model_Service_Quote.php(189): Mage_Core_Model_Resource_Transaction->save()

#15 /chroot/home/removed/removed.com/html/includes/src/Mage_Sales_Model_Service_Quote.php(249): Mage_Sales_Model_Service_Quote->submitOrder()

#16 /chroot/home/removed/removed.com/html/includes/src/Mage_Checkout_Model_Type_Onepage.php(774): Mage_Sales_Model_Service_Quote->submitAll()

#17 /chroot/home/removed/removed.com/html/app/code/core/Mage/Checkout/controllers/OnepageController.php(527): Mage_Checkout_Model_Type_Onepage->saveOrder()

#18 /chroot/home/removed/removed.com/html/includes/src/__default.php(13550): Mage_Checkout_OnepageController->saveOrderAction()

#19 /chroot/home/removed/removed.com/html/includes/src/__default.php(17928): Mage_Core_Controller_Varien_Action->dispatch('saveOrder')

#20 /chroot/home/removed/removed.com/html/includes/src/__default.php(17481): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))

#21 /chroot/home/removed/removed.com/html/includes/src/__default.php(20083): Mage_Core_Controller_Varien_Front->dispatch()

#22 /chroot/home/removed/removed.com/html/app/Mage.php(683): Mage_Core_Model_App->run(Array)

#23 /chroot/home/removed/removed.com/html/index.php(87): Mage::run('', 'store')

#24 {main}

There are about 3 more sections like this, except they start with MageParts_Base_Helper_Mail.php instead of Zend_Mail.

if this were merely an issue of customers not receiving e-mails, it would be fairly minor, but Magento is not allowed those customers to buy anything on the website at all. It seems to be connected to specific accounts, but there's no way to see which ones or why.

[Fooman]

MageParts_Confirmcustomer is a custom extension which looks to be part of the email sending process. I'd suggest getting in touch with the developer of this extension to see if they have come across this behaviour before. If it is possible to disable the extension you try if doing that allows you to place the order with the same email address to see if the order goes through. If it does it would confirm that the issue is indeed coming from the use of MageParts_Confirmcustomer.

[webdizzier]

Did you find the solution to your problem?  I also use Authorize.net, and I'm getting this message when trying to place an order:  "Attention:  Cannot place order", but it doesn't say why and Authorize.net says the problem isn't on their end, so I may have a similar problem as you had.  Thanks.