diff --git a/product/dropkick.tests/Tasks/WinService/PasswordPromptSpecs.cs b/product/dropkick.tests/Tasks/WinService/PasswordPromptSpecs.cs
index 48236a3b..f1156d55 100644
--- a/product/dropkick.tests/Tasks/WinService/PasswordPromptSpecs.cs
+++ b/product/dropkick.tests/Tasks/WinService/PasswordPromptSpecs.cs
@@ -18,11 +18,6 @@ public void It_should_not_prompt_for_password()
 			_result.Results.Where(x => x.Message.Contains("prompt for a password")).Count().ShouldBeEqualTo(0);
 		}
 		
-		public void It_should_prompt_for_password_if_not_supplied()
-		{
-			
-		}
-
 		public override void Context()
 		{
 			_task = new WinServiceCreateTask("localhost", "test");
diff --git a/product/dropkick/Tasks/Topshelf/LocalTopshelfTask.cs b/product/dropkick/Tasks/Topshelf/LocalTopshelfTask.cs
index 855ed731..c2a011d4 100644
--- a/product/dropkick/Tasks/Topshelf/LocalTopshelfTask.cs
+++ b/product/dropkick/Tasks/Topshelf/LocalTopshelfTask.cs
@@ -17,52 +17,57 @@ namespace dropkick.Tasks.Topshelf
     using FileSystem;
     using Prompting;
 
-    public class LocalTopshelfTask :
-        BaseTask
-    {
-        readonly LocalCommandLineTask _task;
-        readonly PromptService _prompt = new ConsolePromptService();
+	public class LocalTopshelfTask :
+		BaseTask
+	{
+		private readonly LocalCommandLineTask _task;
+		private readonly PromptService _prompt = new ConsolePromptService();
 
-        public LocalTopshelfTask(string exeName, string location, string instanceName, string username, string password)
-        {
-            string args = string.IsNullOrEmpty(instanceName)
-                              ? ""
-                              : " /instance:" + instanceName;
+		public LocalTopshelfTask(string exeName, string location, string instanceName, string username, string password)
+		{
+			string args = string.IsNullOrEmpty(instanceName)
+			              	? ""
+			              	: " /instance:" + instanceName;
 
-            if (username != null && password != null)
-            {
-                var user = username;
-                var pass = password;
-                if (username.ShouldPrompt())
-                    user = _prompt.Prompt("Win Service '{0}' UserName".FormatWith(exeName));
-                if (password.ShouldPrompt())
-                    pass = _prompt.Prompt("Win Service '{0}' For User '{1}' Password".FormatWith(exeName, username));
+			if (username != null && password != null)
+			{
+				var user = username;
+				var pass = password;
+				if (username.ShouldPrompt())
+					user = _prompt.Prompt("Win Service '{0}' UserName".FormatWith(exeName));
+				if (shouldPromptForPassword(username, password))
+					pass = _prompt.Prompt("Win Service '{0}' For User '{1}' Password".FormatWith(exeName, username));
 
-                args += " /username:{0} /password:{1}".FormatWith(user, pass);
-            }
+				args += " /username:{0} /password:{1}".FormatWith(user, pass);
+			}
 
-            _task = new LocalCommandLineTask(new DotNetPath(), exeName)
-                        {
-                            Args = "install " + args, 
-                            ExecutableIsLocatedAt = location,
-                            WorkingDirectory = location
-                        };
-        }
+			_task = new LocalCommandLineTask(new DotNetPath(), exeName)
+			        	{
+			        		Args = "install " + args,
+			        		ExecutableIsLocatedAt = location,
+			        		WorkingDirectory = location
+			        	};
+		}
 
-        public override string Name
-        {
-            get { return "[topshelf] local Installing"; }
-        }
+		public override string Name
+		{
+			get { return "[topshelf] local Installing"; }
+		}
 
-        public override DeploymentResult VerifyCanRun()
-        {
-            return _task.VerifyCanRun();
-        }
+		public override DeploymentResult VerifyCanRun()
+		{
+			return _task.VerifyCanRun();
+		}
 
-        public override DeploymentResult Execute()
-        {
-            Logging.Coarse("[topshelf] Installing a local Topshelf service.");
-            return _task.Execute();
-        }
-    }
+		public override DeploymentResult Execute()
+		{
+			Logging.Coarse("[topshelf] Installing a local Topshelf service.");
+			return _task.Execute();
+		}
+
+		private bool shouldPromptForPassword(string username, string password)
+		{
+			return !WindowsAuthentication.IsBuiltInUsername(username) && password.ShouldPrompt();
+		}
+	}
 }
\ No newline at end of file
diff --git a/product/dropkick/Tasks/WinService/WinServiceCreateTask.cs b/product/dropkick/Tasks/WinService/WinServiceCreateTask.cs
index 448a2c79..ceedb5d2 100644
--- a/product/dropkick/Tasks/WinService/WinServiceCreateTask.cs
+++ b/product/dropkick/Tasks/WinService/WinServiceCreateTask.cs
@@ -78,13 +78,7 @@ public override DeploymentResult Execute()
 
     	private bool shouldPromptForPassword()
     	{
-    		return !isBuiltInUsername(UserName) && Password.ShouldPrompt();
-    	}
-
-    	private bool isBuiltInUsername(string userName)
-    	{
-			const string ntAuthorityPrefix = @"NT AUTHORITY\";
-    		return String.Compare(ntAuthorityPrefix, 0, userName, 0, ntAuthorityPrefix.Length, true) == 0;
+    		return !WindowsAuthentication.IsBuiltInUsername(UserName) && Password.ShouldPrompt();
     	}
     }
 }
\ No newline at end of file
diff --git a/product/dropkick/WindowsAuthentication.cs b/product/dropkick/WindowsAuthentication.cs
new file mode 100644
index 00000000..07458336
--- /dev/null
+++ b/product/dropkick/WindowsAuthentication.cs
@@ -0,0 +1,12 @@
+namespace dropkick
+{
+	public static class WindowsAuthentication
+	{
+		public static bool IsBuiltInUsername(string username)
+		{
+			const string ntAuthorityPrefix = @"NT AUTHORITY\";
+
+			return string.Compare(ntAuthorityPrefix, 0, username, 0, ntAuthorityPrefix.Length, true) == 0;			
+		}
+	}
+}
diff --git a/product/dropkick/dropkick.csproj b/product/dropkick/dropkick.csproj
index 1075831d..806498af 100644
--- a/product/dropkick/dropkick.csproj
+++ b/product/dropkick/dropkick.csproj
@@ -312,6 +312,7 @@
     <Compile Include="Engine\Runner.cs" />
     <Compile Include="Configuration\Dsl\ProtoTask.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="WindowsAuthentication.cs" />
     <Compile Include="Wmi\ErrorControl.cs" />
     <Compile Include="Wmi\ProcessReturnCode.cs" />
     <Compile Include="Wmi\ServiceReturnCode.cs" />