Vagrant expand_path: incompatible character encodings: UTF-8 and Windows-1252

I think the problem is because my Pc-User has a "special character" Benny®. This is what the cmd says:

This is my Vagrantfile:

Vagrant.configure("2") do |config|
  config.vm.box = "leopard/rwtrusty64"

  config.vm.network "forwarded_port", guest: 3000, host: 3000
  config.vm.network "private_network", ip: "192.168.33.10"
  config.vm.synced_folder "C:/Users/Benny®/Documents/projects", "/home/vagrant/rails"

  config.vm.provider "virtualbox" do |vb|

   vb.memory = "2054"
  end
end

So, what can I do to fix this problem without changing the user.