Unfortunately I'm running WordPress 3.4.2 on a Windows Server (2008 R2). It's a long story, but I have no choice.
I'm running the XML Sitemap Generator plugin (3.2.8), and it rebuilds the sitemap successfully whenever we add a new post to the blog. The problem is that we can't add any "additional pages" or change the basic or advanced options. Whenever we change the options or add an additional page and then click "update options," the page refreshes, and none of the updates get saved.
This happened when we moved from one dedicated server to another back in October, and we can't figure out what happened during the changeover. Even stranger is that another blog on our server (with the exact same version of WordPress and the exact same version of the plugin) is updating the sitemap correctly.
I've tried reinstalling the plugin and deactivating other plugins to make sure there aren't any conflicts, and that hasn't worked.
If anyone has any suggestions, or would like additional info, please let me know. I'm getting desperate!