diff --git a/TGServerService/Administration.cs b/TGServerService/Administration.cs
index bc9f171782..80caa90f7b 100644
--- a/TGServerService/Administration.cs
+++ b/TGServerService/Administration.cs
@@ -14,6 +14,8 @@ namespace TGServerService
 		object authLock = new object();
 		string LastSeenUser = null;
 
+		readonly SecurityIdentifier ServiceSID = WindowsIdentity.GetCurrent().User;
+
 		/// <inheritdoc />
 		public string GetCurrentAuthorizedGroup()
 		{
@@ -34,7 +36,7 @@ namespace TGServerService
 		/// <inheritdoc />
 		public string SetAuthorizedGroup(string groupName)
 		{
-			if(groupName == null)
+			if (groupName == null)
 			{
 				TheDroidsWereLookingFor = null;
 				var config = Properties.Settings.Default;
@@ -75,41 +77,29 @@ namespace TGServerService
 		//This does NOT validate the windows account, that is done when the user connects internally
 		protected override bool CheckAccessCore(OperationContext operationContext)
 		{
-			if (operationContext.EndpointDispatcher.ContractName == typeof(ITGConnectivity).Name)   //always allow connectivity checks
+			var contract = operationContext.EndpointDispatcher.ContractName;
+
+			if (contract == typeof(ITGConnectivity).Name)   //always allow connectivity checks
 				return true;
 
 			var windowsIdent = operationContext.ServiceSecurityContext.WindowsIdentity;
+
+			if (contract == typeof(ITGInterop).Name)	//only allow the same user the service is running as to use interop, because that's what DD is running as
+				return windowsIdent.User == ServiceSID;
+
 			var wp = new WindowsPrincipal(windowsIdent);
 			//first allow admins
 			var authSuccess = wp.IsInRole(WindowsBuiltInRole.Administrator);
 
 			//if we're not an admin, check that we aren't trying to access the admin interface
 			if (!authSuccess && operationContext.EndpointDispatcher.ContractName != typeof(ITGAdministration).Name && TheDroidsWereLookingFor != null)
-			{
-				var pc = new PrincipalContext(ContextType.Machine);
-				var up = UserPrincipal.FindByIdentity(pc, IdentityType.Sid, windowsIdent.User.Value);
-				//tiny bit of ad support here just cause i was debugging at work
-				//if up is null check it on a domain
-				if (up == null)
-					try
-					{
-						up = UserPrincipal.FindByIdentity(new PrincipalContext(ContextType.Domain), IdentityType.Sid, windowsIdent.User.Value);
-					}
-					catch { }
-				if (up != null)
-				{
-					var gp = GroupPrincipal.FindByIdentity(pc, IdentityType.Sid, TheDroidsWereLookingFor.Value);
-					if (gp != null)
-					{
-						//and allow those in the authorized group
-						authSuccess = up.IsMemberOf(gp);
-					}
-				}
-			}
+				authSuccess = wp.IsInRole(new SecurityIdentifier(Properties.Settings.Default.AuthorizedGroupSID));
+
 			lock (authLock)
 			{
-				var user = operationContext.ServiceSecurityContext.WindowsIdentity.Name;
-				if (LastSeenUser != user) {
+				var user = windowsIdent.Name;
+				if (LastSeenUser != user)
+				{
 					LastSeenUser = user;
 					TGServerService.WriteAccess(user, authSuccess);
 				}
diff --git a/TGServerService/Interop.cs b/TGServerService/Interop.cs
index 121a762479..f176a8a374 100644
--- a/TGServerService/Interop.cs
+++ b/TGServerService/Interop.cs
@@ -11,7 +11,7 @@ using TGServiceInterface;
 namespace TGServerService
 {
 	//handles talking between the world and us
-	partial class TGStationServer : ITGServiceBridge
+	partial class TGStationServer : ITGInterop
 	{
 
 		object topicLock = new object();
diff --git a/TGServiceInterface/ServiceBridge.cs b/TGServiceInterface/Interop.cs
similarity index 93%
rename from TGServiceInterface/ServiceBridge.cs
rename to TGServiceInterface/Interop.cs
index 764250ea36..fa5581f70b 100644
--- a/TGServiceInterface/ServiceBridge.cs
+++ b/TGServiceInterface/Interop.cs
@@ -10,7 +10,7 @@ namespace TGServiceInterface
 	/// Used by DD to access the interop API with call()()
 	/// </summary>
 	[ServiceContract]
-	public interface ITGServiceBridge
+	public interface ITGInterop
 	{
 		/// <summary>
 		/// Called from /world/ExportService(command)
@@ -36,7 +36,7 @@ namespace TGServiceInterface
 		{
 			try
 			{
-				ChannelFactory<ITGServiceBridge> channel = null;
+				ChannelFactory<ITGInterop> channel = null;
 				try
 				{
 					Server.GetComponentAndChannel(out channel).InteropMessage(String.Join(" ", args));
diff --git a/TGServiceInterface/Server.cs b/TGServiceInterface/Server.cs
index 888f216561..0d735c161c 100644
--- a/TGServiceInterface/Server.cs
+++ b/TGServiceInterface/Server.cs
@@ -10,7 +10,7 @@ namespace TGServiceInterface
 		/// <summary>
 		/// List of types that can be used with GetComponen
 		/// </summary>
-		public static readonly IList<Type> ValidInterfaces = new List<Type> { typeof(ITGByond), typeof(ITGChat), typeof(ITGCompiler), typeof(ITGConfig), typeof(ITGDreamDaemon), typeof(ITGRepository), typeof(ITGSService), typeof(ITGConnectivity), typeof(ITGAdministration), typeof(ITGServiceBridge) };
+		public static readonly IList<Type> ValidInterfaces = new List<Type> { typeof(ITGByond), typeof(ITGChat), typeof(ITGCompiler), typeof(ITGConfig), typeof(ITGDreamDaemon), typeof(ITGRepository), typeof(ITGSService), typeof(ITGConnectivity), typeof(ITGAdministration), typeof(ITGInterop) };
 
 		/// <summary>
 		/// Base name of the communication pipe
diff --git a/TGServiceInterface/TGServiceInterface.csproj b/TGServiceInterface/TGServiceInterface.csproj
index 6851600e9c..864ffc9a7b 100644
--- a/TGServiceInterface/TGServiceInterface.csproj
+++ b/TGServiceInterface/TGServiceInterface.csproj
@@ -57,7 +57,7 @@
     <Compile Include="Server.cs" />
     <Compile Include="..\Version.cs" />
     <Compile Include="Service.cs" />
-    <Compile Include="ServiceBridge.cs" />
+    <Compile Include="Interop.cs" />
   </ItemGroup>
   <ItemGroup>
     <Content Include="tgs.ico" />