This error occurs when the user gets to the final step in the Magento Onepage checkout: the order review. When they click the submit button the page loads for a few seconds and then a Javascript alert box is displayed with the message 'undefined'. Not only does this destroy the trust a customer has in your website, it actually stops them from completing the purchase. This means you are losing money and customers! Unfortunately there is no quick generic fix for this but hopefully, by explaining the cause and a way to identify the error, you will be able to overcome this on your own.......

What is Cron? To quote Wikipedia, 'cron is a time-based job scheduler in Unix-like operating systems.' It functions similarly to Windows Task Scheduler in that it allows you to specify actions to be ran after a certain interval. This can be useful for running daily backups or deleting your logs at the end of every month. Where is Cron Used in Magento? By default, cron is used in Magento for various things such as keeping your catalog indexes up to date and refreshing catalog price rules. Cron jobs can also be set up for custom modules, which we will cover shortly. D......

While Javascript form validation shouldn't be your only form of defense with regards to user input, it definitely improves the usability and efficiency of a site. It can also give your site a web 2.0 feel - which users seem to love. Javascript Validation in Magento By default Magento uses a file called form.js (js/varien/form.js) to provide abstract Javascript functions for forms. The most useful application of this class - in my opinion - is the form validation. To achieve this validation, form.js uses the Validation class which is part of the Prototype Javascript library. It ......

There are many ways to mass update product attributes in Magento, each well suited to a different purpose. Magento's built-in mass product attribute updater is great if you want to modify a selection of products or the new attribute value is the same for all products you want to edit. Alternatively, if you wish to alter the attributes in more dynamic ways, updating them programmatic ally via PHP is probably a better way. The downside to both of these methods is speed, with each product update taking a few seconds to complete. While this time can be dramatically reduced by disabling ind......

The Entity, Attribute and Value (EAV) database architecture is at first, extremely difficult to grasp. Combine this with the lack of documentation on EAV and you find that most people don't truly appreciate just how good EAV is and more importantly, how well suited it is to Magento. In this article I will attempt to shed some light on EAV in the hopes of helping you understand how it works, why it works and how this knowledge can benefit you as a Magento developer. To better understand this article, I recommend opening up a development Magento database using a tool such as phpMyAdmin. ......

A newer, better version of this post has been written. Category Navigation Listings in Magento eCommerce The majority of Magento websites out there list their top level categories as well as the current categories sub-categories. This feature is commonly requested on forums so I decided to write a small post about it. Rather than just write out the code, I will show you a few variations so that you can get the right one for you. All of the following code samples can be copy and pasted into ANY template file and will function correctly. Display Top Level Categories Only ......

Since Magento 1.3.2.4, there are have been significant improvements to the Magento template system. While these improvements make creating templates much more efficient, developers are struggling to understand the changes and therefore, to create new themes. Rather than explaining these changes one by one, I will go through each step to creating a theme and discuss each point as it arises. In this article I will be showing you how to create your own custom theme for Magento 1.4. Rather than creating a totally bespoke theme, we will create a theme based on the default theme. However, by......

Easily integrate your WordPress blog with your Magento eCommerce store in a matter of minutes with this free Magento community extension. The module works with 1.3.*, 1.4* and 1.5.* versions of Magento as well as the Professional and Enterprise editions. Installation Choose which installation method is best for you, check the change log or the release archive. Install WordPress Magento Connect Manual Install Version Compatibility Rele......

Magento's use of data models provide a great way to access and modify data. Using aptly named methods and clever abstraction, Varien hide away the complex SQL needed to perform data operations. While this makes learning models easier, it often impacts the speed of the operation and therefore the responsiveness of your site. This is especially true when saving models that use the EAV architecture. More often that not, this cannot be avoided, however there are some situations where executing direct SQL queries would be simpler and much quicker. An example of this is updating product pric......

When I first needed to access a collection of countries in Magento I assumed it would work like all other data collections but was shocked to find that this wasn't the case. Rather than store country data in the database, Magento stores country data in an XML file and loads it in on each request. Fortunately though, there are some simple functions that we can use to access country names and codes in Magento. Get An Array of Country Names/Codes in Magento ? 1 2 3 4 5 ......