Please check your Permalinks settings, and if not already, please change to "Post Name"
See video - http://screencast.com/t/oFv7MmcNGb
Even if they are set to "Post Name", go ahead and re-save to reset.
Additionally, you will want to verify that all of the WP-Client Theme Link Pages are correctly installed and linked in WP-Client-->Settings-->Theme Link Pages (You should see green checkmarks next to all of the boxes)
See example screenshot HERE