Here's the debug output ... still not sure what the issue is though as I don't really understand the debug:
INFO runner: 1 hooks defined.
INFO runner: Running action: #<Vagrant::Action::Builder:0x43bce40>
INFO warden: Calling IN action: #<Vagrant::Action::Builtin::IsState:0x43ed968>
DEBUG is_state: Checking if machine state is 'not_created'
INFO machine: New machine ID: nil
DEBUG is_state: -- Machine state: not_created
INFO warden: Calling OUT action: #<Vagrant::Action::Builtin::IsState:0x43ed968>
INFO runner: Preparing hooks for middleware sequence...
INFO runner: 1 hooks defined.
INFO runner: Running action: #<Vagrant::Action::Warden:0x44b9218>
INFO warden: Calling IN action: #<Proc:0x45991c8@C:/HashiCorp/Vagrant/embedded/gems/gems/vagrant-1.6.2/lib/vagrant/action/warden.rb
:94 (lambda)>
INFO warden: Calling IN action: #<Proc:0x44b9170@C:/HashiCorp/Vagrant/embedded/gems/gems/vagrant-1.6.2/lib/vagrant/action/warden.rb
:94 (lambda)>
INFO warden: Calling IN action: #<VagrantPlugins::DockerProvider::Action::HostMachineBuildDir:0x46d5458>
INFO warden: Calling IN action: #<VagrantPlugins::DockerProvider::Action::HostMachineSyncFolders:0x4701060>
DEBUG environment: Attempting to acquire process-lock: af1c9f26ffaaeb3c90a19f8d872a5069
DEBUG environment: Attempting to acquire process-lock: dotlock
INFO environment: Acquired process lock: dotlock
INFO environment: Released process lock: dotlock
INFO environment: Acquired process lock: af1c9f26ffaaeb3c90a19f8d872a5069
INFO interface: output: Syncing folders to the host VM...
INFO interface: output: ==> default: Syncing folders to the host VM...