Archives widget linking to blank pages

Hi there,

I have an Archives widget in the footer at the bottom of my blog but when you click on the month link, it links through to a blank page instead of the posts from that month.

Any ideas why that might be?

The blog is here: http://www.seedlightpictures.com/category/blog/
Archives list is at the bottom right corner.

This is an example of one of the links:
http://www.seedlightpictures.com/2013/07/

Thanks!