diff --git a/plugins/provisioners/shell/provisioner.rb b/plugins/provisioners/shell/provisioner.rb
index 9aaee60de..257c68d63 100644
--- a/plugins/provisioners/shell/provisioner.rb
+++ b/plugins/provisioners/shell/provisioner.rb
@@ -4,11 +4,14 @@ require "tempfile"
 require "vagrant/util/downloader"
 require "vagrant/util/retryable"
 
+require "pry-byebug"
 module VagrantPlugins
   module Shell
     class Provisioner < Vagrant.plugin("2", :provisioner)
       include Vagrant::Util::Retryable
 
+      DEFAULT_WINDOWS_SHELL_EXT = ".ps1".freeze
+
       def provision
         args = ""
         if config.args.is_a?(String)
@@ -135,16 +138,14 @@ module VagrantPlugins
           # Upload the script to the machine
           @machine.communicate.tap do |comm|
             env = config.env.map{|k,v| comm.generate_environment_export(k, v)}.join(';')
-            shell = comm.machine_config_ssh.shell
-            if File.extname(upload_path).empty?
-              remote_ext = File.extname(path)[1..-1]
-              if !remote_ext
-                remote_ext = @machine.config.winssh.shell == "cmd" ? "bat" : "ps1"
-              end
-              upload_path << ".#{remote_ext}"
+            remote_ext = File.extname(path)
+            if remote_ext.empty?
+              remote_ext = @machine.config.winssh.shell == "cmd" ? ".bat" : ".ps1"
             end
+
+            remote_path = add_extension(upload_path(), remote_ext)
             if remote_ext == "bat"
-              command = "#{env}\n cmd.exe /c \"#{upload_path}\" #{args}"
+              command = "#{env}\n cmd.exe /c \"#{remote_path}\" #{args}"
             else
               # Copy powershell_args from configuration
               shell_args = config.powershell_args
@@ -152,7 +153,7 @@ module VagrantPlugins
               shell_args += " -ExecutionPolicy Bypass" if config.powershell_args !~ /[-\/]ExecutionPolicy/i
               # CLIXML output is kinda useless, especially on non-windows hosts
               shell_args += " -OutputFormat Text" if config.powershell_args !~ /[-\/]OutputFormat/i
-              command = "#{env}\npowershell #{shell_args} -file \"#{upload_path}\"#{args}"
+              command = "#{env}\npowershell #{shell_args} -file \"#{remote_path}\"#{args}"
             end
 
             # Reset upload path permissions for the current ssh user
@@ -161,8 +162,8 @@ module VagrantPlugins
               info = @machine.ssh_info
               raise Vagrant::Errors::SSHNotReady if info.nil?
             end
-
-            comm.upload(path.to_s, upload_path)
+            
+            comm.upload(path.to_s, remote_path)
 
             if config.name
               @machine.ui.detail(I18n.t("vagrant.provisioners.shell.running",
@@ -198,10 +199,7 @@ module VagrantPlugins
           @machine.communicate.tap do |comm|
             # Make sure that the upload path has an extension, since
             # having an extension is critical for Windows execution
-            winrm_upload_path = upload_path
-            if File.extname(winrm_upload_path) == ""
-              winrm_upload_path += File.extname(path.to_s)
-            end
+            winrm_upload_path = add_extension(upload_path, DEFAULT_WINDOWS_SHELL_EXT)
 
             # Upload it
             comm.upload(path.to_s, winrm_upload_path)
@@ -260,6 +258,11 @@ module VagrantPlugins
         "#{quote}#{text.gsub(/#{quote}/) { |m| "#{m}\\#{m}#{m}" }}#{quote}"
       end
 
+      def add_extension(path, ext)
+        return path if !File.extname(path.to_s).empty?
+        path + ext
+      end
+
       # This method yields the path to a script to upload and execute
       # on the remote server. This method will properly clean up the
       # script file if needed.
diff --git a/test/unit/plugins/provisioners/shell/provisioner_test.rb b/test/unit/plugins/provisioners/shell/provisioner_test.rb
index dd83c42e4..03556fcf9 100644
--- a/test/unit/plugins/provisioners/shell/provisioner_test.rb
+++ b/test/unit/plugins/provisioners/shell/provisioner_test.rb
@@ -456,12 +456,46 @@ describe "Vagrant::Shell::Provisioner" do
       allow(machine).to receive(:communicate).and_return(communicator)
       allow(machine).to receive(:guest).and_return(guest)
       allow(machine).to receive(:ui).and_return(ui)
-      allow(vsp).to receive(:with_script_file).and_yield(config.path)
     }
 
     it "ensures that files are uploaded with an extension" do
+      allow(vsp).to receive(:with_script_file).and_yield(config.path)
       expect(communicator).to receive(:upload).with(config.path, /arbitrary.ps1$/)
       vsp.send(:provision_winrm, "")
     end
+
+    context "inline option set" do
+      let(:config) {
+        double(
+          :config,
+          :args                            => "doesn't matter",
+          :env                             => {},
+          :remote?                         => false,
+          :inline                          => "some commands",
+          :upload_path                     => nil,
+          :path                            => nil,
+          :binary                          => false,
+          :md5                             => nil,
+          :sha1                            => 'EXPECTED_VALUE',
+          :sha256                          => nil,
+          :sha384                          => nil,
+          :sha512                          => nil,
+          :reset                           => false,
+          :reboot                          => false,
+          :powershell_args                 => "",
+          :name                            => nil,
+          :privileged                      => false,
+          :powershell_elevated_interactive => false
+        )
+      }
+  
+      it "creates an executable with an extension" do
+        default_path = "C:/tmp/vagrant-shell"
+        allow(vsp).to receive(:with_script_file).and_yield(default_path)
+        allow(communicator).to receive(:upload).with(default_path, /vagrant-shell/)
+        expect(communicator).to receive(:sudo).with(/vagrant-shell.ps1/, anything)
+        vsp.send(:provision_winrm, "")
+      end
+    end
   end
 end