I tried to change my urls on my wordpress from the default to “/%postname%/”, but when I did this, the blog posts and pages all disappeared. It gave me the error message saying the pages/posts didn’t exist.
From the format of the URL’s for permalinks you showed in the other thread, I would suspect the blog you are talking about is self-hosted using the software downloaded from wordpress.org since that is not the form found here at wordpress.com.
The format here is: http://yourblogname.wordpress.com/2007/11/26/postname/ or similar. If you are asking about a self-hosted blog, any answers we would give you here will not really be correct. With the software from wordpress.org you can choose the format of your permalinks, and the default is what you indicated in the other post.
Your blog here only has one post, and the permalink format is as I described above.