Suddenly getting: Could not instantiate mail function error

I have been pouring over the forum for a few hours (unable to find an answer to my problem/situation) and finally decided to post my question. My site has been running pretty much flawlessly (well with exception of a crappy host a few years ago) and love ZenCart. This morning I had order emails waiting as I do most mornings, along with PayPal payment notifications. About noon I received a payment email but no order email, didn't think too much of it as sometimes it does come in slower. I was filling orders, and when I came back from the post office there were 2 more PayPal payment emails with no order emails. I decided to send my 'Shipped' emails first and discovered the problem. The first update I tried appended the comments, however gave me an error of:

ERROR: Failed sending email to: "XXX XXXXXX" with subject: "Order Update #44614" Could not instantiate mail function. Please check Admin->Configuration->Email Options->Email Transport.

I tried another record update and received the same error.

Additionally, the Contact Us page appears to send the email, however they never arrive. I have another ZenCart 1.5.1 site hosted on the same server and it is working correctly with customer updates and the Contact Us page.

I have not changed any settings on my ZenCart in months, well with exception of the PayPal Express module about a month ago, though nothing else. I contacted my host, they did some tests and said the PHP was running as it is supposed to and confirmed they had done no recent software updates or configuration modifications.

I am running 1.5.1 on a Linux server
PHP Version 5.3.22
MySQL 5.1.68-cll

The website is http://hatnpatch.com

Thanks in advance for helping, I know your time is valuable.

Have you read the similar threads posted below??

Kobra,
I must have missed the one where Dr Byte talked about the SMTPAUTH bypassing everything as it is the one that worked. The whole thing was just odd, how it was working fine under PHP, the ISP did no changes and it just failed. I actually thought maybe it was a corrupt file or more. To anyone reading this, the SMTPAUTH is the way to go if you can. Also, get 'real' hosting as I used to be on super cheap hosting like GD and it's easier to pay extra and have your site WORK than all the headaches that come with it.

Thanks and sorry!

Was this problem ever solved. I am getting the same error.

jodean:

Was this problem ever solved. I am getting the same error.

Would appear that for the OP the solution was to change from transport mode of PHP to SMTPAUTH (and enter the appropriate credentials) based on their last post.

Remember to ask your host if you need to use secure settings and what they are for smtpauth, PCI Compliance is getting to be hard to work with and servers that are set up and are compliant no longer let cleartext information or ports be open