Problem to include category /

Hello, I have a problem to include category / the links, you may only configuration, but do not know how to include category / categories before.
Is giving 404 error when clicking on the links:

The right would http://www.criarsites.me / category / categoryname/posts

But is this:

http://www.criarsites.me / categoryname / posts.

how can I fix?

http://ww.wp.xz.cn/extend/plugins/breadcrumb-navxt/