Blocksy Theme

hi
after I installed Blocksy theme to my new word press it makes it crash and when I submit any post it doesn`t want to publish anything and a message appear: “your link is expired”,
I log in again and it doesn`t publish and said I need higher authority permission.
I uninstalled WordPress and reinstall it. and to my shock I find the theme installed already I try to delete it deny me any action.
I hate it !!!!
I hope you can help me.