When I tried to change from default permalinks to /%category%/%postname%/ all my images in my header disappeared except on the homepage of my blog. My posts also came up 404 under categories, though showed correctly when clicked from the homepage.
I was able to get posts and header images to reappear when I reverted to default and did a quick edit on all posts.
Any suggestions on what could have caused that and what I can do to have both header images and permalinks working? That's so key to SEO, and I want to get it resolved before I have dozens or hundred of posts to manually reset.