We are asked this question quite a bit, so I wanted to post it here…
If you’re struggling to understand why your abandoned cart emails are not working, and you’re also using a one step checkout process, it’s because they are conflicting. It’s a lot like putting a humidifier and a dehumidifier into the same room, and let them battle it out.
In Magento, there is core code that manages the extremely complex systems, including displaying content on the home page, calculating pricing on category and product pages, handling discounts, shipping, payment methods, and doing all of this in a secure way.
Extensions can “extend” the functionality of Magento.
A One Page Checkout extensions can change the default way that the checkout process works. This is one of the more invasive extensions, as it completely changes how the entire checkout system works.
Instead of using Magento’s default system, it uses it’s own system.
One page checkouts can work and work well on some sites. But they do have bugs in them, especially if an end users uses a form fill system in their browser.
The built-in Magento checkout process, according to testing, tends to perform better from an overall conversion perspective.
The issue, though, is that if you’d like to use an abandoned cart email system, that extension uses the default Magento way of handling a partial cart.
It wasn’t designed to work with the one page checkout, so outbound emails will likely not work, as it’s trying to integrate with the native Magento functionality and was not designed to function in tandem with a modified checkout process.
This is just one example of many, but our experience shows that this is very difficult to do without modifying the functionality of the one page checkout system itself.