**Permalinks Migration**
„http://www.deanlee.cn/wordpress/permalinks-migration-plugin/“:http://www.deanlee.cn/wordpress/permalinks-migration-plugin/
„http://wordpress.org/extend/plugins/permalinks-migration-plugin-for-wordpress/“:http://wordpress.org/extend/plugins/permalinks-migration-plugin-for-wordpress/
With this plugin, you can safely change your permalink structure – for example, from */%year%/%monthnum%/%day%/%postname%/* to */%category%/%postname%/* – without breaking the old links to your website, and even doesn’t affect your search engine rankings.
But doing so will make all pages indexed by search engines become invalid, moreover, losing visitors from other sites or bookmarks that links to you.
Permalinks Migration plugin is a way to tell the search engines (and browsers) that the page has permenantly moved, and that the old address should be replaced by the new one . This plugin will generates a “301 Redirect” when user or spider visit your site through old permalinks and redirect them to the new permalinks of the same post.
