I imported posts from another blog into WordPress (on my own server). Everything worked perfect. When I switched to the Customize Permalink Structure, URLs to older posts stopped working. My custom structure is /%postname%/. For the posts that didn't work, the URL is being changed to the post name with spaces between the words. For the posts that do work the URL is being changed to the post name separated with dashes. If I go into a post that doesn't work and simply resave it. It then begins to rewrite to the post name with dashes and works.
Is there a way to re-save all posts to fix this problem?
Any other suggestions?