SEBWIN-219: Basic startup sequence is now working.

SafeExamBrowser.Client/App.cs

@@ -7,7 +7,6 @@
  */
 
 using System;
-using System.ComponentModel;
 using System.Threading;
 using System.Windows;
 
@@ -56,14 +55,16 @@ namespace SafeExamBrowser.Client
 		{
 			base.OnStartup(e);
 
+			ShutdownMode = ShutdownMode.OnMainWindowClose;
+
 			instances.BuildObjectGraph();
+			instances.LogStartupInformation();
 
 			var success = instances.ClientController.TryStart();
 
 			if (success)
 			{
 				MainWindow = instances.Taskbar;
-				MainWindow.Closing += MainWindow_Closing;
 				MainWindow.Show();
 			}
 			else
@@ -72,10 +73,12 @@ namespace SafeExamBrowser.Client
 			}
 		}
 
-		private void MainWindow_Closing(object sender, CancelEventArgs e)
+		protected override void OnExit(ExitEventArgs e)
 		{
-			MainWindow?.Hide();
 			instances.ClientController.Terminate();
+			instances.LogShutdownInformation();
+
+			base.OnExit(e);
 		}
 	}
 }

SafeExamBrowser.Client/Communication/ClientHost.cs

@@ -17,10 +17,13 @@ namespace SafeExamBrowser.Client.Communication
 {
 	internal class ClientHost : BaseHost, IClientHost
 	{
+		private int processId;
+
 		public Guid StartupToken { private get; set; }
 
-		public ClientHost(string address, ILogger logger) : base(address, logger)
+		public ClientHost(string address, ILogger logger, int processId) : base(address, logger)
 		{
+			this.processId = processId;
 		}
 
 		protected override bool OnConnect(Guid? token)
@@ -36,13 +39,19 @@ namespace SafeExamBrowser.Client.Communication
 		protected override Response OnReceive(Message message)
 		{
 			// TODO
-			return null;
+
+			return new SimpleResponse(SimpleResponsePurport.UnknownMessage);
 		}
 
-		protected override Response OnReceive(MessagePurport message)
+		protected override Response OnReceive(SimpleMessagePurport message)
 		{
-			// TODO
+			switch (message)
-			return null;
+			{
+				case SimpleMessagePurport.Authenticate:
+					return new AuthenticationResponse { ProcessId = processId };
+			}
+
+			return new SimpleResponse(SimpleResponsePurport.UnknownMessage);
 		}
 	}
 }

SafeExamBrowser.Client/CompositionRoot.cs

@@ -8,6 +8,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using SafeExamBrowser.Browser;
 using SafeExamBrowser.Client.Behaviour;
 using SafeExamBrowser.Client.Behaviour.Operations;
@@ -37,6 +38,10 @@ namespace SafeExamBrowser.Client
 {
 	internal class CompositionRoot
 	{
+		private string logFilePath;
+		private string runtimeHostUri;
+		private Guid startupToken;
+
 		private ClientConfiguration configuration;
 		private ILogger logger;
 		private INativeMethods nativeMethods;
@@ -49,21 +54,19 @@ namespace SafeExamBrowser.Client
 
 		internal void BuildObjectGraph()
 		{
-			var args = Environment.GetCommandLineArgs();
+			ValidateCommandLineArguments();
-
-			Validate(args);
 
 			configuration = new ClientConfiguration();
 			logger = new Logger();
 			nativeMethods = new NativeMethods();
 			systemInfo = new SystemInfo();
 
-			InitializeLogging(args[1]);
+			InitializeLogging();
 
 			text = new Text(logger);
 			uiFactory = new UserInterfaceFactory(text);
 
-			var runtimeProxy = new RuntimeProxy(args[2], new ModuleLogger(logger, typeof(RuntimeProxy)));
+			var runtimeProxy = new RuntimeProxy(runtimeHostUri, new ModuleLogger(logger, typeof(RuntimeProxy)));
 			var displayMonitor = new DisplayMonitor(new ModuleLogger(logger, typeof(DisplayMonitor)), nativeMethods);
 			var processMonitor = new ProcessMonitor(new ModuleLogger(logger, typeof(ProcessMonitor)), nativeMethods);
 			var windowMonitor = new WindowMonitor(new ModuleLogger(logger, typeof(WindowMonitor)), nativeMethods);
@@ -73,25 +76,38 @@ namespace SafeExamBrowser.Client
 			var operations = new Queue<IOperation>();
 
 			operations.Enqueue(new I18nOperation(logger, text));
-			operations.Enqueue(new RuntimeConnectionOperation(logger, runtimeProxy, Guid.Parse(args[3])));
+			operations.Enqueue(new RuntimeConnectionOperation(logger, runtimeProxy, startupToken));
 			operations.Enqueue(new ConfigurationOperation(configuration, logger, runtimeProxy));
 			operations.Enqueue(new DelayedInitializationOperation(BuildCommunicationHostOperation));
-			operations.Enqueue(new DelayedInitializationOperation(BuildKeyboardInterceptorOperation));
+			// TODO
-			operations.Enqueue(new WindowMonitorOperation(logger, windowMonitor));
+			//operations.Enqueue(new DelayedInitializationOperation(BuildKeyboardInterceptorOperation));
-			operations.Enqueue(new ProcessMonitorOperation(logger, processMonitor));
+			//operations.Enqueue(new WindowMonitorOperation(logger, windowMonitor));
+			//operations.Enqueue(new ProcessMonitorOperation(logger, processMonitor));
 			operations.Enqueue(new DisplayMonitorOperation(displayMonitor, logger, Taskbar));
 			operations.Enqueue(new DelayedInitializationOperation(BuildTaskbarOperation));
 			operations.Enqueue(new DelayedInitializationOperation(BuildBrowserOperation));
 			operations.Enqueue(new ClipboardOperation(logger, nativeMethods));
-			operations.Enqueue(new DelayedInitializationOperation(BuildMouseInterceptorOperation));
+			//operations.Enqueue(new DelayedInitializationOperation(BuildMouseInterceptorOperation));
 
 			var sequence = new OperationSequence(logger, operations);
 
 			ClientController = new ClientController(displayMonitor, logger, sequence, processMonitor, runtimeProxy, Taskbar, windowMonitor);
 		}
 
-		private void Validate(string[] args)
+		internal void LogStartupInformation()
 		{
+			logger.Log($"# New client instance started at {DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff")}");
+			logger.Log(string.Empty);
+		}
+
+		internal void LogShutdownInformation()
+		{
+			logger?.Log($"# Client instance terminated at {DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff")}");
+		}
+
+		private void ValidateCommandLineArguments()
+		{
+			var args = Environment.GetCommandLineArgs();
 			var hasFour = args?.Length == 4;
 
 			if (hasFour)
@@ -102,16 +118,20 @@ namespace SafeExamBrowser.Client
 
 				if (hasLogfilePath && hasHostUri && hasToken)
 				{
+					logFilePath = args[1];
+					runtimeHostUri = args[2];
+					startupToken = Guid.Parse(args[3]);
+
 					return;
 				}
 			}
 
-			throw new ArgumentException("Invalid parameters! Required: SafeExamBrowser.Client.exe <logfile path> <host URI> <token>");
+			throw new ArgumentException("Invalid arguments! Required: SafeExamBrowser.Client.exe <logfile path> <host URI> <token>");
 		}
 
-		private void InitializeLogging(string filePath)
+		private void InitializeLogging()
 		{
-			var logFileWriter = new LogFileWriter(new DefaultLogFormatter(), filePath);
+			var logFileWriter = new LogFileWriter(new DefaultLogFormatter(), logFilePath);
 
 			logFileWriter.Initialize();
 			logger.Subscribe(logFileWriter);
@@ -128,9 +148,12 @@ namespace SafeExamBrowser.Client
 
 		private IOperation BuildCommunicationHostOperation()
 		{
-			var host = new ClientHost(configuration.RuntimeInfo.ClientAddress, new ModuleLogger(logger, typeof(ClientHost)));
+			var processId = Process.GetCurrentProcess().Id;
+			var host = new ClientHost(configuration.RuntimeInfo.ClientAddress, new ModuleLogger(logger, typeof(ClientHost)), processId);
 			var operation = new CommunicationOperation(host, logger);
 
+			host.StartupToken = startupToken;
+
 			return operation;
 		}
 

SafeExamBrowser.Configuration/ConfigurationRepository.cs

@@ -73,6 +73,9 @@ namespace SafeExamBrowser.Configuration
 			};
 
 			settings.Browser.StartUrl = "https://www.duckduckgo.com";
+			settings.Taskbar.AllowApplicationLog = true;
+			settings.Taskbar.AllowKeyboardLayout = true;
+			settings.Taskbar.AllowWirelessNetwork = true;
 
 			CurrentSettings = settings;
 

SafeExamBrowser.Contracts/Communication/ICommunication.cs

@@ -19,6 +19,7 @@ namespace SafeExamBrowser.Contracts.Communication
 	[ServiceKnownType(typeof(AuthenticationResponse))]
 	[ServiceKnownType(typeof(ConfigurationResponse))]
 	[ServiceKnownType(typeof(ClientConfiguration))]
+	[ServiceKnownType(typeof(SimpleResponse))]
 	public interface ICommunication
 	{
 		/// <summary>

SafeExamBrowser.Contracts/Communication/ICommunicationHost.cs

@@ -20,11 +20,13 @@ namespace SafeExamBrowser.Contracts.Communication
 		/// <summary>
 		/// Starts the host and opens it for communication.
 		/// </summary>
+		/// <exception cref="System.ServiceModel.CommunicationException">If the host fails to start.</exception>
 		void Start();
 
 		/// <summary>
 		/// Closes and terminates the host.
 		/// </summary>
+		/// <exception cref="System.ServiceModel.CommunicationException">If the host fails to terminate.</exception>
 		void Stop();
 	}
 }

SafeExamBrowser.Contracts/Communication/Messages/Message.cs

@@ -17,5 +17,10 @@ namespace SafeExamBrowser.Contracts.Communication.Messages
 		/// The communication token needed for authentication.
 		/// </summary>
 		public Guid CommunicationToken { get; set; }
+
+		public override string ToString()
+		{
+			return GetType().Name;
+		}
 	}
 }

SafeExamBrowser.Contracts/Communication/Messages/SimpleMessage.cs

@@ -16,6 +16,16 @@ namespace SafeExamBrowser.Contracts.Communication.Messages
 		/// <summary>
 		/// The purport of the message.
 		/// </summary>
-		public MessagePurport Purport { get; set; }
+		public SimpleMessagePurport Purport { get; set; }
+
+		public SimpleMessage(SimpleMessagePurport purport)
+		{
+			Purport = purport;
+		}
+
+		public override string ToString()
+		{
+			return $"{base.ToString()} -> {Purport}";
+		}
 	}
 }

SafeExamBrowser.Contracts/Communication/Messages/SimpleMessagePurport.cs

@@ -11,7 +11,7 @@ using System;
 namespace SafeExamBrowser.Contracts.Communication.Messages
 {
 	[Serializable]
-	public enum MessagePurport
+	public enum SimpleMessagePurport
 	{
 		/// <summary>
 		/// Requests an interlocutor to submit data for authentication.

SafeExamBrowser.Contracts/Communication/Responses/AuthenticationResponse.cs

@@ -16,6 +16,6 @@ namespace SafeExamBrowser.Contracts.Communication.Responses
 		/// <summary>
 		/// The process identifier used for authentication.
 		/// </summary>
-		public int ProcessId { get; }
+		public int ProcessId { get; set; }
 	}
 }

SafeExamBrowser.Contracts/Communication/Responses/Response.cs

@@ -13,5 +13,9 @@ namespace SafeExamBrowser.Contracts.Communication.Responses
 	[Serializable]
 	public class Response
 	{
+		public override string ToString()
+		{
+			return GetType().Name;
+		}
 	}
 }

SafeExamBrowser.Contracts/Communication/Responses/SimpleResponse.cs

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2018 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+using System;
+
+namespace SafeExamBrowser.Contracts.Communication.Responses
+{
+	[Serializable]
+	public class SimpleResponse : Response
+	{
+		/// <summary>
+		/// The purport of the response.
+		/// </summary>
+		public SimpleResponsePurport Purport { get; set; }
+
+		public SimpleResponse(SimpleResponsePurport purport)
+		{
+			Purport = purport;
+		}
+
+		public override string ToString()
+		{
+			return $"{base.ToString()} -> {Purport}";
+		}
+	}
+}

SafeExamBrowser.Contracts/Communication/Responses/SimpleResponsePurport.cs

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2018 ETH Zürich, Educational Development and Technology (LET)
+ * 
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+using System;
+
+namespace SafeExamBrowser.Contracts.Communication.Responses
+{
+	[Serializable]
+	public enum SimpleResponsePurport
+	{
+		/// <summary>
+		/// Signals an interlocutor that a message has been understood.
+		/// </summary>
+		Acknowledged = 1,
+
+		/// <summary>
+		/// Signals an interlocutor that a message has not been understood.
+		/// </summary>
+		UnknownMessage
+	}
+}

SafeExamBrowser.Contracts/SafeExamBrowser.Contracts.csproj

@@ -66,13 +66,15 @@
     <Compile Include="Communication\IServiceProxy.cs" />
     <Compile Include="Communication\Messages\Message.cs" />
     <Compile Include="Communication\Messages\DisconnectionMessage.cs" />
-    <Compile Include="Communication\Messages\MessagePurport.cs" />
+    <Compile Include="Communication\Messages\SimpleMessagePurport.cs" />
     <Compile Include="Communication\Messages\SimpleMessage.cs" />
     <Compile Include="Communication\Responses\AuthenticationResponse.cs" />
     <Compile Include="Communication\Responses\ConfigurationResponse.cs" />
     <Compile Include="Communication\Responses\ConnectionResponse.cs" />
     <Compile Include="Communication\Responses\DisconnectionResponse.cs" />
     <Compile Include="Communication\Responses\Response.cs" />
+    <Compile Include="Communication\Responses\SimpleResponsePurport.cs" />
+    <Compile Include="Communication\Responses\SimpleResponse.cs" />
     <Compile Include="Configuration\ClientConfiguration.cs" />
     <Compile Include="Configuration\RuntimeInfo.cs" />
     <Compile Include="Configuration\ISession.cs" />

SafeExamBrowser.Core/Communication/BaseHost.cs

@@ -8,6 +8,7 @@
 
 using System;
 using System.ServiceModel;
+using System.Threading;
 using SafeExamBrowser.Contracts.Communication;
 using SafeExamBrowser.Contracts.Communication.Messages;
 using SafeExamBrowser.Contracts.Communication.Responses;
@@ -18,16 +19,26 @@ namespace SafeExamBrowser.Core.Communication
 	[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Single)]
 	public abstract class BaseHost : ICommunication, ICommunicationHost
 	{
+		private const int TWO_SECONDS = 2000;
+		private readonly object @lock = new object();
+
 		private string address;
 		private ILogger logger;
 		private ServiceHost host;
+		private Thread hostThread;
 
 		protected Guid? CommunicationToken { get; private set; }
 		protected ILogger Logger { get; private set; }
 
 		public bool IsRunning
 		{
-			get { return host?.State == CommunicationState.Opened; }
+			get
+			{
+				lock (@lock)
+				{
+					return host?.State == CommunicationState.Opened;
+				}
+			}
 		}
 
 		public BaseHost(string address, ILogger logger)
@@ -39,86 +50,111 @@ namespace SafeExamBrowser.Core.Communication
 		protected abstract bool OnConnect(Guid? token);
 		protected abstract void OnDisconnect();
 		protected abstract Response OnReceive(Message message);
-		protected abstract Response OnReceive(MessagePurport message);
+		protected abstract Response OnReceive(SimpleMessagePurport message);
 
 		public ConnectionResponse Connect(Guid? token = null)
 		{
-			logger.Debug($"Received connection request with authentication token '{token}'.");
+			lock (@lock)
-
-			var response = new ConnectionResponse();
-			var connected = OnConnect(token);
-
-			if (connected)
 			{
-				response.CommunicationToken = CommunicationToken = Guid.NewGuid();
+				logger.Debug($"Received connection request with authentication token '{token}'.");
-				response.ConnectionEstablished = true;
+
+				var response = new ConnectionResponse();
+				var connected = OnConnect(token);
+
+				if (connected)
+				{
+					response.CommunicationToken = CommunicationToken = Guid.NewGuid();
+					response.ConnectionEstablished = true;
+				}
+
+				logger.Debug($"{(connected ? "Accepted" : "Denied")} connection request.");
+
+				return response;
 			}
-
-			logger.Debug($"{(connected ? "Accepted" : "Denied")} connection request.");
-
-			return response;
 		}
 
 		public DisconnectionResponse Disconnect(DisconnectionMessage message)
 		{
-			var response = new DisconnectionResponse();
+			lock (@lock)
-
-			// TODO: Compare with ToString in BaseProxy - needed?
-			logger.Debug($"Received disconnection request with message '{message}'.");
-
-			if (IsAuthorized(message?.CommunicationToken))
 			{
-				OnDisconnect();
+				var response = new DisconnectionResponse();
 
-				CommunicationToken = null;
+				logger.Debug($"Received disconnection request with message '{ToString(message)}'.");
-				response.ConnectionTerminated = true;
+
+				if (IsAuthorized(message?.CommunicationToken))
+				{
+					OnDisconnect();
+
+					CommunicationToken = null;
+					response.ConnectionTerminated = true;
+				}
+
+				return response;
 			}
-
-			return response;
 		}
 
 		public Response Send(Message message)
 		{
-			Response response = null;
+			lock (@lock)
-
-			logger.Debug($"Received message '{message}'.");
-
-			if (IsAuthorized(message?.CommunicationToken))
 			{
-				if (message is SimpleMessage)
+				Response response = null;
+
+				logger.Debug($"Received message '{ToString(message)}'.");
+
+				if (IsAuthorized(message?.CommunicationToken))
 				{
-					response = OnReceive((message as SimpleMessage).Purport);
+					if (message is SimpleMessage)
-				}
+					{
-				else
+						response = OnReceive((message as SimpleMessage).Purport);
-				{
+					}
-					response = OnReceive(message);
+					else
+					{
+						response = OnReceive(message);
+					}
 				}
+
+				logger.Debug($"Sending response '{ToString(response)}'.");
+
+				return response;
 			}
-
-			logger.Debug($"Sending response '{response}'.");
-
-			return response;
 		}
 
 		public void Start()
 		{
-			host = new ServiceHost(this);
+			lock (@lock)
-			host.AddServiceEndpoint(typeof(ICommunication), new NetNamedPipeBinding(NetNamedPipeSecurityMode.Transport), address);
+			{
-			host.Closed += Host_Closed;
+				var exception = default(Exception);
-			host.Closing += Host_Closing;
+				var startedEvent = new AutoResetEvent(false);
-			host.Faulted += Host_Faulted;
-			host.Opened += Host_Opened;
-			host.Opening += Host_Opening;
-			host.UnknownMessageReceived += Host_UnknownMessageReceived;
-			host.Open();
 
-			logger.Debug($"Successfully started communication host for endpoint '{address}'.");
+				hostThread = new Thread(() => TryStartHost(startedEvent, out exception));
+				hostThread.SetApartmentState(ApartmentState.STA);
+				hostThread.IsBackground = true;
+				hostThread.Start();
+
+				var success = startedEvent.WaitOne(TWO_SECONDS);
+
+				if (!success)
+				{
+					throw new CommunicationException($"Failed to start communication host for endpoint '{address}' within {TWO_SECONDS / 1000} seconds!", exception);
+				}
+			}
 		}
 
 		public void Stop()
 		{
-			host?.Close();
+			lock (@lock)
-			logger.Debug($"Terminated communication host for endpoint '{address}'.");
+			{
+				var success = TryStopHost(out Exception exception);
+
+				if (success)
+				{
+					logger.Debug($"Terminated communication host for endpoint '{address}'.");
+				}
+				else
+				{
+					throw new CommunicationException($"Failed to terminate communication host for endpoint '{address}'!", exception);
+				}
+			}
 		}
 
 		private bool IsAuthorized(Guid? token)
@@ -126,6 +162,52 @@ namespace SafeExamBrowser.Core.Communication
 			return CommunicationToken == token;
 		}
 
+		private void TryStartHost(AutoResetEvent startedEvent, out Exception exception)
+		{
+			exception = null;
+
+			try
+			{
+				host = new ServiceHost(this);
+				host.AddServiceEndpoint(typeof(ICommunication), new NetNamedPipeBinding(NetNamedPipeSecurityMode.Transport), address);
+				host.Closed += Host_Closed;
+				host.Closing += Host_Closing;
+				host.Faulted += Host_Faulted;
+				host.Opened += Host_Opened;
+				host.Opening += Host_Opening;
+				host.UnknownMessageReceived += Host_UnknownMessageReceived;
+				host.Open();
+
+				logger.Debug($"Successfully started communication host for endpoint '{address}'.");
+
+				startedEvent.Set();
+			}
+			catch (Exception e)
+			{
+				exception = e;
+			}
+		}
+
+		private bool TryStopHost(out Exception exception)
+		{
+			var success = false;
+
+			exception = null;
+
+			try
+			{
+				host?.Close();
+				success = hostThread.Join(TWO_SECONDS);
+			}
+			catch (Exception e)
+			{
+				exception = e;
+				success = false;
+			}
+
+			return success;
+		}
+
 		private void Host_Closed(object sender, EventArgs e)
 		{
 			logger.Debug("Communication host has been closed.");
@@ -155,5 +237,15 @@ namespace SafeExamBrowser.Core.Communication
 		{
 			logger.Debug($"Communication host has received an unknown message: {e?.Message}.");
 		}
+
+		private string ToString(Message message)
+		{
+			return message != null ? message.ToString() : "<null>";
+		}
+
+		private string ToString(Response response)
+		{
+			return response != null ? response.ToString() : "<null>";
+		}
 	}
 }

SafeExamBrowser.Core/Communication/BaseProxy.cs

@@ -40,7 +40,7 @@ namespace SafeExamBrowser.Core.Communication
 			(channel as ICommunicationObject).Opened += BaseProxy_Opened;
 			(channel as ICommunicationObject).Opening += BaseProxy_Opening;
 
-			Logger.Debug($"Trying to connect to endpoint {address} with authentication token '{token}'...");
+			Logger.Debug($"Trying to connect to endpoint {address}{(token.HasValue ? $" with authentication token '{token}'" : string.Empty)}...");
 
 			var response = channel.Connect(token);
 
@@ -70,21 +70,14 @@ namespace SafeExamBrowser.Core.Communication
 
 			var response = channel.Send(message);
 
-			Logger.Debug($"Sent {ToString(message)}, got {ToString(response)}.");
+			Logger.Debug($"Sent message '{ToString(message)}', got response '{ToString(response)}'.");
 
 			return response;
 		}
 
-		protected Response Send(MessagePurport purport)
+		protected Response Send(SimpleMessagePurport purport)
 		{
-			FailIfNotConnected(nameof(Send));
+			return Send(new SimpleMessage(purport));
-
-			var message = new SimpleMessage { Purport = purport };
-			var response = channel.Send(message);
-
-			Logger.Debug($"Sent {ToString(message)}, got {ToString(response)}.");
-
-			return response;
 		}
 
 		private void BaseProxy_Closed(object sender, EventArgs e)
@@ -132,12 +125,12 @@ namespace SafeExamBrowser.Core.Communication
 
 		private string ToString(Message message)
 		{
-			return message != null ? $"message of type '{message.GetType()}'" : "no message";
+			return message != null ? message.ToString() : "<null>";
 		}
 
 		private string ToString(Response response)
 		{
-			return response != null ? $"response of type '{response.GetType()}'" : "no response";
+			return response != null ? response.ToString() : "<null>";
 		}
 	}
 }

SafeExamBrowser.Core/Communication/ClientProxy.cs

@@ -21,7 +21,9 @@ namespace SafeExamBrowser.Core.Communication
 
 		public AuthenticationResponse RequestAuthentication()
 		{
-			return (AuthenticationResponse) Send(MessagePurport.ClientIsReady);
+			var response = Send(SimpleMessagePurport.Authenticate);
+
+			return response as AuthenticationResponse;
 		}
 	}
 }

SafeExamBrowser.Core/Communication/RuntimeProxy.cs

@@ -22,12 +22,12 @@ namespace SafeExamBrowser.Core.Communication
 
 		public ClientConfiguration GetConfiguration()
 		{
-			return ((ConfigurationResponse) Send(MessagePurport.ConfigurationNeeded)).Configuration;
+			return ((ConfigurationResponse) Send(SimpleMessagePurport.ConfigurationNeeded)).Configuration;
 		}
 
 		public void InformClientReady()
 		{
-			Send(MessagePurport.ClientIsReady);
+			Send(SimpleMessagePurport.ClientIsReady);
 		}
 	}
 }

SafeExamBrowser.Core/Logging/Logger.cs

@@ -81,6 +81,15 @@ namespace SafeExamBrowser.Core.Logging
 			details.AppendLine();
 			details.AppendLine(exception.StackTrace);
 
+			for (var inner = exception.InnerException; inner != null; inner = inner.InnerException)
+			{
+				details.AppendLine();
+				details.AppendLine($"   Inner Exception Message: {inner.Message}");
+				details.AppendLine($"   Inner Exception Type: {inner.GetType()}");
+				details.AppendLine();
+				details.AppendLine(inner.StackTrace);
+			}
+
 			Add(LogLevel.Error, message);
 			Add(new LogText(details.ToString()));
 		}

SafeExamBrowser.Runtime/Behaviour/Operations/SessionSequenceOperation.cs

@@ -104,19 +104,19 @@ namespace SafeExamBrowser.Runtime.Behaviour.Operations
 		{
 			const int TEN_SECONDS = 10000;
 
-			var clientReady = new AutoResetEvent(false);
+			var clientStarted = false;
-			var clientReadyHandler = new CommunicationEventHandler(() => clientReady.Set());
+			var clientReadyEvent = new AutoResetEvent(false);
+			var clientReadyEventHandler = new CommunicationEventHandler(() => clientReadyEvent.Set());
 			var clientExecutable = configuration.RuntimeInfo.ClientExecutablePath;
 			var clientLogFile = $"{'"' + configuration.RuntimeInfo.ClientLogFile + '"'}";
 			var hostUri = configuration.RuntimeInfo.RuntimeAddress;
 			var token = session.StartupToken.ToString("D");
 
-			runtimeHost.ClientReady += clientReadyHandler;
+			runtimeHost.ClientReady += clientReadyEventHandler;
 			session.ClientProcess = processFactory.StartNew(clientExecutable, clientLogFile, hostUri, token);
 
-			var clientStarted = clientReady.WaitOne(TEN_SECONDS);
+			clientStarted = clientReadyEvent.WaitOne(TEN_SECONDS);
-
+			runtimeHost.ClientReady -= clientReadyEventHandler;
-			runtimeHost.ClientReady -= clientReadyHandler;
 
 			// TODO: Check if client process alive!
 			if (clientStarted)
@@ -126,7 +126,7 @@ namespace SafeExamBrowser.Runtime.Behaviour.Operations
 					var response = client.RequestAuthentication();
 
 					// TODO: Further integrity checks necessary?
-					if (session.ClientProcess.Id == response.ProcessId)
+					if (session.ClientProcess.Id == response?.ProcessId)
 					{
 						sessionRunning = true;
 					}

SafeExamBrowser.Runtime/Communication/RuntimeHost.cs

@@ -7,7 +7,6 @@
  */
 
 using System;
-using System.Threading.Tasks;
 using SafeExamBrowser.Contracts.Communication;
 using SafeExamBrowser.Contracts.Communication.Messages;
 using SafeExamBrowser.Contracts.Communication.Responses;
@@ -43,21 +42,21 @@ namespace SafeExamBrowser.Runtime.Communication
 		protected override Response OnReceive(Message message)
 		{
 			// TODO
-			return null;
+			return new SimpleResponse(SimpleResponsePurport.UnknownMessage);
 		}
 
-		protected override Response OnReceive(MessagePurport message)
+		protected override Response OnReceive(SimpleMessagePurport message)
 		{
 			switch (message)
 			{
-				case MessagePurport.ClientIsReady:
+				case SimpleMessagePurport.ClientIsReady:
 					ClientReady?.Invoke();
-					break;
+					return new SimpleResponse(SimpleResponsePurport.Acknowledged);
-				case MessagePurport.ConfigurationNeeded:
+				case SimpleMessagePurport.ConfigurationNeeded:
 					return new ConfigurationResponse { Configuration = configuration.BuildClientConfiguration() };
 			}
 
-			return null;
+			return new SimpleResponse(SimpleResponsePurport.UnknownMessage);
 		}
 	}
 }

SafeExamBrowser.SystemComponents/WirelessNetwork.cs

@@ -23,6 +23,7 @@ namespace SafeExamBrowser.SystemComponents
 	public class WirelessNetwork : ISystemComponent<ISystemWirelessNetworkControl>
 	{
 		private const int TWO_SECONDS = 2000;
+		private readonly object @lock = new object();
 
 		private ISystemWirelessNetworkControl control;
 		private ILogger logger;
@@ -144,7 +145,7 @@ namespace SafeExamBrowser.SystemComponents
 
 		private void UpdateControl()
 		{
-			lock (networks)
+			lock (@lock)
 			{
 				try
 				{

SafeExamBrowser.UserInterface.Classic/RuntimeWindow.xaml

@@ -5,7 +5,7 @@
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:local="clr-namespace:SafeExamBrowser.UserInterface.Classic"
         xmlns:s="clr-namespace:System;assembly=mscorlib"
-        mc:Ignorable="d" Background="White" Foreground="White" Height="500" Width="750" WindowStyle="None" WindowStartupLocation="CenterScreen"
+        mc:Ignorable="d" Background="White" Foreground="White" Height="500" Width="850" WindowStyle="None" WindowStartupLocation="CenterScreen"
         Icon="./Images/SafeExamBrowser.ico" ResizeMode="NoResize" Title="Safe Exam Browser" Topmost="True">
     <Grid>
         <Border x:Name="AnimatedBorder" Panel.ZIndex="10" BorderBrush="DodgerBlue" BorderThickness="5" Visibility="{Binding AnimatedBorderVisibility}">
@@ -36,10 +36,10 @@
                 <Grid Grid.Row="0">
                     <Grid.ColumnDefinitions>
                         <ColumnDefinition Width="*" />
-                        <ColumnDefinition Width="350" />
+                        <ColumnDefinition Width="400" />
                     </Grid.ColumnDefinitions>
                     <Image Grid.Column="0" Grid.ColumnSpan="2" Margin="-25,0,0,0" Source="pack://application:,,,/SafeExamBrowser.UserInterface.Classic;component/Images/SplashScreen.png" />
-                    <TextBlock x:Name="InfoTextBlock" Grid.Column="1" Foreground="Gray" Margin="10,75,175,10" TextWrapping="Wrap" />
+                    <TextBlock x:Name="InfoTextBlock" Grid.Column="1" Foreground="Gray" Margin="10,75,225,10" TextWrapping="Wrap" />
                 </Grid>
                 <ProgressBar x:Name="ProgressBar" Grid.Row="1" Background="WhiteSmoke" BorderThickness="0" Foreground="DodgerBlue"
                              IsIndeterminate="{Binding IsIndeterminate}" Maximum="{Binding MaxProgress}" Value="{Binding CurrentProgress}"