Here are 3 quick solutions to try if you do not see your Magento store categories after a fresh install of Magento or an upgrade to the latest version. I wanted to post this because I just recently helped install Magento for someone and experienced this. The installation version was the latest Magento version, 1.2.1.2 and product categories did not show up on the frontend after they were added in the administration interface.
The top 3 solutions to this in my experience are:

The categories not added as sub-categories of the Default, …

Magento Vertical Menu using Peter Hamilton’s code
In one of our premium Magento themes we implemented a vertical category menu with the code adapted from this thread. It’s quite easy to implement and to make it even easier for others, we decided to write a step by step tutorial.

Add a new block type in “catalog.xml” file
Create a new phtml file and name it “leftnav.phtml”, place it inside catalog/navigation
Edit CSS

Add a new block type in “catalog.xml” file
Here we presume you want to have the vertical category menu shows up on every page, …

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Magento is the open-source Ecommerce platform promising a magnificent revolution in the industry. Magento was designed with the concept that each Ecommerce implementation has to be unique since no two businesses are alike. Magento’s modular architecture puts the control back in the hands of the online merchant and places no constraints on business processes and flow.
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I was installing Magento 1.3.2.1 in my Windows XP computer. I am using Xampp. I encountered the following errors during the installation.
PHP Extension “curl” must be loaded
PHP Extension “mcrypt” must be loaded
PHP Extension “pdo_mysql” must be loaded
I googled and the answer was to load the extension in php.ini file. In xampp, there are two places where php.ini file is found. It is present inside php folder and inside apache/bin folder. You can load extensions mentioned in the above error by changing the php.ini file. Search for curl, mcrypt and pdo_mysql …