The Cache location can be changed by adding the "browser.cache.disk.parent_directory" preference and entering a folder path. To do it, type about:config in the Firefox address bar. Right click your mouse and select New String from the Menu. In the dialog box, just type in browser.cache.disk.parent_directory as the preference name and the new path to the cache location, for instance d:\temp. Once this preference is specified, a new directory named "Cache" will be created at the path you set.