I’m facing a really strange problem. I wrote a custom product importer, based on different other importers. The importer is working fine.
I can import the products and they are showing up on the Front-End and Back-End. But after the importer adds images to the products, the products are suddenly not showing up anymore in the Front-End. All the lists with products are empty if it expects products with images.
Of course I refreshed all the cache and indexes.
Fixed it with installing php5-gd, found the solution on http://codepoets.co.uk/2011/magento-not-finding-product-images-solution/