type of content (dexp_portfolio) deleted after installing xml sitemap


after installing and enable xml-sitemap module, type of content (dexp_portfolio) was deleted.

The type of content will be deleted! Or better is no longer visible because in the database (node_type) type there is! but the content (node) can not edit! In content list the nodes have not description!
if you try a new fresh installation and installed and enabled xmlsitemap the content dexp_portfolio disappears.
I look a your answer, thank you.