If you’re using the newer version of Magento (1.13+ I believe) you’ll find that you’re unable to manually process certain indexes through the Magento admin. You’ll need to manually run these indexes using the shell script within Magento.

You can run the following commands within your Magento root

However on your installation you may have other custom indexes added by 3rd party modules, to list all available indexes you can run:

You’re then able to run any index listed in the response with, replacing INDEX_CODE with the code for the index from the above response

If you’re wanting to reindex all indexes after some form of data import or mass action you can run the following code

If you’re wanting to gain further knowledge you can run the indexer with the help option as follows

If you’re wanting to learn more about the indexing system in Magento you can visit the following URL: http://www.magentocommerce.com/knowledge-base/entry/ee113-indexing

Dave Macaulay
Dave Macaulay
I'm an enthusiastic, slightly eccentric Magento developer who bores with the idea of another basic brief.