Problem using rails_upgrade

I am trying to run rake rails:upgrade:check but it gives:

rake aborted!
no such file to load – vendor/plugins/hoe

If I look in vendor/plugins/ hoe is there and the permissions are
correct.

What is going on?

Now the terminal says

rake aborted!
no such file to load – vendor/plugins/rails_upgrade

From googling I know other people have had this problem but I can’t find
an answer. What am I doing wrong??