I just set the blog up with the Google webmaster tools when I saw your post. So it’s been up for only 2 hours, but it’s not coming up with any errors.
I don’t see a category.php file in the theme editor.
I also just noticed that the tag links are also pulling up a blank page as well.
Thanks for the advice. I did do a live preview of the theme and the category links work (so that means that the the category was the problem?). But I’d really rather not change my theme.
Is there somewhere I can look in the code to figure out why the URL is pulling up a blank page in my current theme?