diff --git a/config/default.rb b/config/default.rb
index f3d0bdf4d..2e96ea9d2 100644
--- a/config/default.rb
+++ b/config/default.rb
@@ -19,7 +19,6 @@ Vagrant::Config.run do |config|
   config.vm.box_url = nil
   config.vm.base_mac = nil
   config.vm.forward_port("ssh", 22, 2222, :auto => true)
-  config.vm.disk_image_format = 'VMDK'
   config.vm.boot_mode = "vrdp"
   config.vm.system = :linux
 
diff --git a/lib/vagrant/config/vm.rb b/lib/vagrant/config/vm.rb
index 63304c253..aed5294a1 100644
--- a/lib/vagrant/config/vm.rb
+++ b/lib/vagrant/config/vm.rb
@@ -19,7 +19,6 @@ module Vagrant
       attr_reader :shared_folders
       attr_reader :network_options
       attr_reader :provisioners
-      attr_accessor :disk_image_format
       attr_accessor :system
 
       def initialize