diff --git a/lib/vagrant-env/config.rb b/lib/vagrant-env/config.rb
index f8a79c9..cd3a515 100644
--- a/lib/vagrant-env/config.rb
+++ b/lib/vagrant-env/config.rb
@@ -8,7 +8,7 @@ class Config < Vagrant.plugin("2", :config)
       # config.env.enable __FILE__
       def enable(vagrantfile = nil)
         if vagrantfile
-          load File.dirname(vagrantfile) + '/.env'
+          load File.join File.dirname(vagrantfile), '.env'
         else
           # The default is .env in the current directory - but that may not be
           # the same directory that the Vagrantfile is in