SEBWIN-353: Fixed bug with service session not being terminated when startup is aborted. Removed ignore flag from service proxy, as it did not serve any real purpose.

SafeExamBrowser.Communication.Contracts/Proxies/IServiceProxy.cs

@@ -16,12 +16,6 @@ namespace SafeExamBrowser.Communication.Contracts.Proxies
 	/// </summary>
 	public interface IServiceProxy : ICommunicationProxy
 	{
-		/// <summary>
-		/// Instructs the proxy to ignore all operations or simulate a connection, where applicable. To be set e.g. when the service
-		/// policy is optional and the service is not available.
-		/// </summary>
-		bool Ignore { set; }
-
 		/// <summary>
 		/// Instructs the service to start a system configuration update.
 		/// </summary>

SafeExamBrowser.Communication.UnitTests/Proxies/ServiceProxyTests.cs

@@ -47,24 +47,6 @@ namespace SafeExamBrowser.Communication.UnitTests.Proxies
 			sut.Connect();
 		}
 
-		[TestMethod]
-		public void MustIgnoreConnectIfUnavailable()
-		{
-			sut.Ignore = true;
-			sut.Connect();
-
-			proxy.Verify(p => p.Connect(It.IsAny<Guid>()), Times.Never);
-		}
-
-		[TestMethod]
-		public void MustIgnoreDisconnectIfUnavailable()
-		{
-			sut.Ignore = true;
-			sut.Disconnect();
-
-			proxy.Verify(p => p.Disconnect(It.IsAny<DisconnectionMessage>()), Times.Never);
-		}
-
 		[TestMethod]
 		public void MustCorrectlySendSystemConfigurationUpdate()
 		{
@@ -87,15 +69,6 @@ namespace SafeExamBrowser.Communication.UnitTests.Proxies
 			Assert.IsFalse(communication.Success);
 		}
 
-		[TestMethod]
-		public void MustIgnoreSystemConfigurationUpdateIfUnavailable()
-		{
-			sut.Ignore = true;
-			sut.RunSystemConfigurationUpdate();
-
-			proxy.Verify(p => p.Send(It.IsAny<Message>()), Times.Never);
-		}
-
 		[TestMethod]
 		public void MustCorrectlyStartSession()
 		{
@@ -120,17 +93,6 @@ namespace SafeExamBrowser.Communication.UnitTests.Proxies
 			Assert.IsFalse(communication.Success);
 		}
 
-		[TestMethod]
-		public void MustIgnoreStartSessionIfUnavaiable()
-		{
-			sut.Ignore = true;
-
-			var communication = sut.StartSession(null);
-
-			Assert.IsTrue(communication.Success);
-			proxy.Verify(p => p.Send(It.IsAny<Message>()), Times.Never);
-		}
-
 		[TestMethod]
 		public void MustCorrectlyStopSession()
 		{
@@ -154,16 +116,5 @@ namespace SafeExamBrowser.Communication.UnitTests.Proxies
 
 			Assert.IsFalse(communication.Success);
 		}
-
-		[TestMethod]
-		public void MustIgnoreStopSessionIfUnavaiable()
-		{
-			sut.Ignore = true;
-
-			var communication = sut.StopSession(Guid.Empty);
-
-			Assert.IsTrue(communication.Success);
-			proxy.Verify(p => p.Send(It.IsAny<Message>()), Times.Never);
-		}
 	}
 }

SafeExamBrowser.Communication/Proxies/ServiceProxy.cs

@@ -20,39 +20,12 @@ namespace SafeExamBrowser.Communication.Proxies
 	/// </summary>
 	public class ServiceProxy : BaseProxy, IServiceProxy
 	{
-		public bool Ignore { private get; set; }
-
 		public ServiceProxy(string address, IProxyObjectFactory factory, ILogger logger, Interlocutor owner) : base(address, factory, logger, owner)
 		{
 		}
 
-		public override bool Connect(Guid? token = null, bool autoPing = true)
-		{
-			if (IgnoreOperation(nameof(Connect)))
-			{
-				return false;
-			}
-
-			return base.Connect(autoPing: autoPing);
-		}
-
-		public override bool Disconnect()
-		{
-			if (IgnoreOperation(nameof(Disconnect)))
-			{
-				return false;
-			}
-
-			return base.Disconnect();
-		}
-
 		public CommunicationResult RunSystemConfigurationUpdate()
 		{
-			if (IgnoreOperation(nameof(RunSystemConfigurationUpdate)))
-			{
-				return new CommunicationResult(true);
-			}
-
 			try
 			{
 				var response = Send(SimpleMessagePurport.UpdateSystemConfiguration);
@@ -79,11 +52,6 @@ namespace SafeExamBrowser.Communication.Proxies
 
 		public CommunicationResult StartSession(ServiceConfiguration configuration)
 		{
-			if (IgnoreOperation(nameof(StartSession)))
-			{
-				return new CommunicationResult(true);
-			}
-
 			try
 			{
 				var response = Send(new SessionStartMessage(configuration));
@@ -110,11 +78,6 @@ namespace SafeExamBrowser.Communication.Proxies
 
 		public CommunicationResult StopSession(Guid sessionId)
 		{
-			if (IgnoreOperation(nameof(StopSession)))
-			{
-				return new CommunicationResult(true);
-			}
-
 			try
 			{
 				var response = Send(new SessionStopMessage(sessionId));
@@ -138,15 +101,5 @@ namespace SafeExamBrowser.Communication.Proxies
 				return new CommunicationResult(false);
 			}
 		}
-
-		private bool IgnoreOperation(string operationName)
-		{
-			if (Ignore)
-			{
-				Logger.Debug($"Skipping '{operationName}' operation because the ignore flag is set.");
-			}
-
-			return Ignore;
-		}
 	}
 }

SafeExamBrowser.Runtime.UnitTests/Operations/ServiceOperationTests.cs

@@ -13,12 +13,12 @@ using Moq;
 using SafeExamBrowser.Communication.Contracts.Hosts;
 using SafeExamBrowser.Communication.Contracts.Proxies;
 using SafeExamBrowser.Configuration.Contracts;
-using SafeExamBrowser.Settings;
-using SafeExamBrowser.Settings.Service;
 using SafeExamBrowser.Core.Contracts.OperationModel;
 using SafeExamBrowser.Logging.Contracts;
 using SafeExamBrowser.Runtime.Operations;
 using SafeExamBrowser.Runtime.Operations.Events;
+using SafeExamBrowser.Settings;
+using SafeExamBrowser.Settings.Service;
 using SafeExamBrowser.SystemComponents.Contracts;
 using SafeExamBrowser.UserInterface.Contracts.MessageBox;
 
@@ -27,14 +27,11 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 	[TestClass]
 	public class ServiceOperationTests
 	{
-		private AppConfig appConfig;
+		private SessionContext context;
 		private Mock<ILogger> logger;
 		private Mock<IRuntimeHost> runtimeHost;
 		private Mock<IServiceProxy> service;
 		private EventWaitHandle serviceEvent;
-		private SessionConfiguration session;
-		private SessionContext sessionContext;
-		private AppSettings settings;
 		private Mock<IUserInfo> userInfo;
 		private ServiceOperation sut;
 
@@ -43,37 +40,35 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 		{
 			var serviceEventName = $"{nameof(SafeExamBrowser)}-{nameof(ServiceOperationTests)}";
 
-			appConfig = new AppConfig();
 			logger = new Mock<ILogger>();
 			runtimeHost = new Mock<IRuntimeHost>();
 			service = new Mock<IServiceProxy>();
 			serviceEvent = new EventWaitHandle(false, EventResetMode.AutoReset, serviceEventName);
-			session = new SessionConfiguration();
+			context = new SessionContext();
-			sessionContext = new SessionContext();
-			settings = new AppSettings();
 			userInfo = new Mock<IUserInfo>();
 
-			appConfig.ServiceEventName = serviceEventName;
+			context.Current = new SessionConfiguration();
-			sessionContext.Current = session;
+			context.Current.AppConfig = new AppConfig();
-			sessionContext.Current.AppConfig = appConfig;
+			context.Current.AppConfig.ServiceEventName = serviceEventName;
-			sessionContext.Next = session;
+			context.Current.Settings = new AppSettings();
-			sessionContext.Next.AppConfig = appConfig;
+			context.Next = new SessionConfiguration();
-			session.Settings = settings;
+			context.Next.AppConfig = new AppConfig();
-			settings.Service.Policy = ServicePolicy.Mandatory;
+			context.Next.AppConfig.ServiceEventName = serviceEventName;
+			context.Next.Settings = new AppSettings();
 
-			sut = new ServiceOperation(logger.Object, runtimeHost.Object, service.Object, sessionContext, 0, userInfo.Object);
+			sut = new ServiceOperation(logger.Object, runtimeHost.Object, service.Object, context, 0, userInfo.Object);
 		}
 
 		[TestMethod]
 		public void Perform_MustConnectToService()
 		{
 			service.Setup(s => s.Connect(null, true)).Returns(true);
-			settings.Service.Policy = ServicePolicy.Mandatory;
+			context.Next.Settings.Service.Policy = ServicePolicy.Mandatory;
 
 			sut.Perform();
 
 			service.Setup(s => s.Connect(null, true)).Returns(true);
-			settings.Service.Policy = ServicePolicy.Optional;
+			context.Next.Settings.Service.Policy = ServicePolicy.Optional;
 
 			sut.Perform();
 
@@ -83,13 +78,15 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 		[TestMethod]
 		public void Perform_MustStartSessionIfConnected()
 		{
+			context.Next.SessionId = Guid.NewGuid();
+			context.Next.Settings.Service.Policy = ServicePolicy.Optional;
 			service.SetupGet(s => s.IsConnected).Returns(true);
 			service.Setup(s => s.Connect(null, true)).Returns(true);
 			service.Setup(s => s.StartSession(It.IsAny<ServiceConfiguration>())).Returns(new CommunicationResult(true)).Callback(() => serviceEvent.Set());
 
 			var result = sut.Perform();
 
-			service.Verify(s => s.StartSession(It.IsAny<ServiceConfiguration>()), Times.Once);
+			service.Verify(s => s.StartSession(It.Is<ServiceConfiguration>(c => c.SessionId == context.Next.SessionId)), Times.Once);
 			service.Verify(s => s.RunSystemConfigurationUpdate(), Times.Never);
 			userInfo.Verify(u => u.GetUserName(), Times.Once);
 			userInfo.Verify(u => u.GetUserSid(), Times.Once);
@@ -123,7 +120,7 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 			service.Setup(s => s.Connect(null, true)).Returns(true);
 			service.Setup(s => s.StartSession(It.IsAny<ServiceConfiguration>())).Returns(new CommunicationResult(true));
 
-			sut = new ServiceOperation(logger.Object, runtimeHost.Object, service.Object, sessionContext, TIMEOUT, userInfo.Object);
+			sut = new ServiceOperation(logger.Object, runtimeHost.Object, service.Object, context, TIMEOUT, userInfo.Object);
 
 			before = DateTime.Now;
 			var result = sut.Perform();
@@ -138,12 +135,15 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 		[TestMethod]
 		public void Perform_MustNotStartSessionIfNotConnected()
 		{
+			context.Next.Settings.Service.Policy = ServicePolicy.Mandatory;
 			service.SetupGet(s => s.IsConnected).Returns(false);
 			service.Setup(s => s.Connect(null, true)).Returns(false);
 
-			sut.Perform();
+			var result = sut.Perform();
 
 			service.Verify(s => s.StartSession(It.IsAny<ServiceConfiguration>()), Times.Never);
+
+			Assert.AreEqual(OperationResult.Failed, result);
 		}
 
 		[TestMethod]
@@ -165,9 +165,9 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 		{
 			var errorShown = false;
 
+			context.Next.Settings.Service.Policy = ServicePolicy.Mandatory;
 			service.SetupGet(s => s.IsConnected).Returns(false);
 			service.Setup(s => s.Connect(null, true)).Returns(false);
-			settings.Service.Policy = ServicePolicy.Mandatory;
 			sut.ActionRequired += (args) => errorShown = args is MessageEventArgs m && m.Icon == MessageBoxIcon.Error;
 
 			var result = sut.Perform();
@@ -179,13 +179,14 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 		[TestMethod]
 		public void Perform_MustNotFailIfServiceOptionalAndNotAvailable()
 		{
+			context.Next.Settings.Service.Policy = ServicePolicy.Optional;
 			service.SetupGet(s => s.IsConnected).Returns(false);
 			service.Setup(s => s.Connect(null, true)).Returns(false);
-			settings.Service.Policy = ServicePolicy.Optional;
 
 			var result = sut.Perform();
 
-			service.VerifySet(s => s.Ignore = true);
+			service.Verify(s => s.StartSession(It.IsAny<ServiceConfiguration>()), Times.Never);
+
 			Assert.AreEqual(OperationResult.Success, result);
 		}
 
@@ -194,9 +195,9 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 		{
 			var warningShown = false;
 
+			context.Next.Settings.Service.Policy = ServicePolicy.Warn;
 			service.SetupGet(s => s.IsConnected).Returns(false);
 			service.Setup(s => s.Connect(null, true)).Returns(false);
-			settings.Service.Policy = ServicePolicy.Warn;
 			sut.ActionRequired += (args) => warningShown = args is MessageEventArgs m && m.Icon == MessageBoxIcon.Warning;
 
 			var result = sut.Perform();
@@ -208,18 +209,47 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 		[TestMethod]
 		public void Repeat_MustStopCurrentAndStartNewSession()
 		{
-			service.Setup(s => s.StopSession(It.IsAny<Guid>())).Returns(new CommunicationResult(true)).Callback(() => serviceEvent.Set());
+			var order = 0;
-			PerformNormally();
+			var start1 = 0;
+			var stop1 = 0;
+			var start2 = 0;
+			var session1Id = Guid.NewGuid();
+			var session2Id = Guid.NewGuid();
+
+			context.Next.SessionId = session1Id;
+			service.SetupGet(s => s.IsConnected).Returns(true);
+			service.Setup(s => s.Connect(null, true)).Returns(true);
+			service
+				.Setup(s => s.StartSession(It.Is<ServiceConfiguration>(c => c.SessionId == session1Id)))
+				.Returns(new CommunicationResult(true))
+				.Callback(() => { start1 = ++order; serviceEvent.Set(); });
+			service
+				.Setup(s => s.StartSession(It.Is<ServiceConfiguration>(c => c.SessionId == session2Id)))
+				.Returns(new CommunicationResult(true))
+				.Callback(() => { start2 = ++order; serviceEvent.Set(); });
+			service
+				.Setup(s => s.StopSession(It.IsAny<Guid>()))
+				.Returns(new CommunicationResult(true))
+				.Callback(() => { stop1 = ++order; serviceEvent.Set(); });
+
+			sut.Perform();
+
+			context.Current.SessionId = session1Id;
+			context.Next.SessionId = session2Id;
 
 			var result = sut.Repeat();
 
 			service.Verify(s => s.Connect(It.IsAny<Guid?>(), It.IsAny<bool>()), Times.Once);
-			service.Verify(s => s.StopSession(It.IsAny<Guid>()), Times.Once);
+			service.Verify(s => s.StopSession(It.Is<Guid>(id => id == session1Id)), Times.Once);
-			service.Verify(s => s.StartSession(It.IsAny<ServiceConfiguration>()), Times.Exactly(2));
+			service.Verify(s => s.StartSession(It.Is<ServiceConfiguration>(c => c.SessionId == session1Id)), Times.Once);
+			service.Verify(s => s.StartSession(It.Is<ServiceConfiguration>(c => c.SessionId == session2Id)), Times.Once);
 			service.Verify(s => s.Disconnect(), Times.Never);
 			service.Verify(s => s.RunSystemConfigurationUpdate(), Times.Never);
 
 			Assert.AreEqual(OperationResult.Success, result);
+			Assert.IsTrue(start1 == 1);
+			Assert.IsTrue(stop1 == 2);
+			Assert.IsTrue(start2 == 3);
 		}
 
 		[TestMethod]
@@ -229,12 +259,13 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 
 			service.Reset();
 			service.SetupGet(s => s.IsConnected).Returns(false);
-			service.Setup(s => s.Connect(null, true)).Returns(true);
+			service.Setup(s => s.Connect(null, true)).Returns(true).Callback(() => service.SetupGet(s => s.IsConnected).Returns(true));
-			service.Setup(s => s.StopSession(It.IsAny<Guid>())).Returns(new CommunicationResult(true));
+			service.Setup(s => s.StartSession(It.IsAny<ServiceConfiguration>())).Returns(new CommunicationResult(true)).Callback(() => serviceEvent.Set());
 
 			var result = sut.Repeat();
 
 			service.Verify(s => s.Connect(It.IsAny<Guid?>(), It.IsAny<bool>()), Times.Once);
+			service.Verify(s => s.StopSession(It.IsAny<Guid>()), Times.Never);
 
 			Assert.AreEqual(OperationResult.Success, result);
 		}
@@ -264,7 +295,7 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 			var before = default(DateTime);
 
 			service.Setup(s => s.StopSession(It.IsAny<Guid>())).Returns(new CommunicationResult(true));
-			sut = new ServiceOperation(logger.Object, runtimeHost.Object, service.Object, sessionContext, TIMEOUT, userInfo.Object);
+			sut = new ServiceOperation(logger.Object, runtimeHost.Object, service.Object, context, TIMEOUT, userInfo.Object);
 
 			PerformNormally();
 
@@ -279,6 +310,19 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 			Assert.IsTrue(after - before >= new TimeSpan(0, 0, 0, 0, TIMEOUT));
 		}
 
+		[TestMethod]
+		public void Repeat_MustNotStopSessionIfNoSessionRunning()
+		{
+			service.SetupGet(s => s.IsConnected).Returns(true);
+			service.Setup(s => s.StartSession(It.IsAny<ServiceConfiguration>())).Returns(new CommunicationResult(true)).Callback(() => serviceEvent.Set());
+
+			var result = sut.Repeat();
+
+			service.Verify(s => s.StopSession(It.IsAny<Guid>()), Times.Never);
+
+			Assert.AreEqual(OperationResult.Success, result);
+		}
+
 		[TestMethod]
 		public void Revert_MustDisconnect()
 		{
@@ -295,24 +339,6 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 			Assert.AreEqual(OperationResult.Success, result);
 		}
 
-		[TestMethod]
-		public void Revert_MustStopSessionIfConnected()
-		{
-			service.Setup(s => s.Disconnect()).Returns(true);
-			service.Setup(s => s.StopSession(It.IsAny<Guid>())).Returns(new CommunicationResult(true)).Callback(() => serviceEvent.Set());
-			service.Setup(s => s.RunSystemConfigurationUpdate()).Returns(new CommunicationResult(true));
-
-			PerformNormally();
-
-			var result = sut.Revert();
-
-			service.Verify(s => s.StopSession(It.IsAny<Guid>()), Times.Once);
-			service.Verify(s => s.Disconnect(), Times.Once);
-			service.Verify(s => s.RunSystemConfigurationUpdate(), Times.Once);
-
-			Assert.AreEqual(OperationResult.Success, result);
-		}
-
 		[TestMethod]
 		public void Revert_MustHandleCommunicationFailureWhenStoppingSession()
 		{
@@ -369,7 +395,7 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 			var before = default(DateTime);
 
 			service.Setup(s => s.StopSession(It.IsAny<Guid>())).Returns(new CommunicationResult(true));
-			sut = new ServiceOperation(logger.Object, runtimeHost.Object, service.Object, sessionContext, TIMEOUT, userInfo.Object);
+			sut = new ServiceOperation(logger.Object, runtimeHost.Object, service.Object, context, TIMEOUT, userInfo.Object);
 
 			PerformNormally();
 
@@ -391,13 +417,15 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 			var result = sut.Revert();
 
 			service.Verify(s => s.StopSession(It.IsAny<Guid>()), Times.Never);
+
 			Assert.AreEqual(OperationResult.Success, result);
 		}
 
 		[TestMethod]
 		public void Revert_MustNotStopSessionIfNoSessionRunning()
 		{
-			sessionContext.Current = null;
+			context.Current = null;
+			context.Next = null;
 			service.SetupGet(s => s.IsConnected).Returns(true);
 			service.Setup(s => s.Disconnect()).Returns(true);
 
@@ -417,6 +445,50 @@ namespace SafeExamBrowser.Runtime.UnitTests.Operations
 			Assert.AreEqual(OperationResult.Success, result);
 		}
 
+		[TestMethod]
+		public void Revert_MustStopSessionIfConnected()
+		{
+			context.Next.SessionId = Guid.NewGuid();
+			service.Setup(s => s.Disconnect()).Returns(true);
+			service.Setup(s => s.StopSession(It.IsAny<Guid>())).Returns(new CommunicationResult(true)).Callback(() => serviceEvent.Set());
+			service.Setup(s => s.RunSystemConfigurationUpdate()).Returns(new CommunicationResult(true));
+
+			PerformNormally();
+
+			var result = sut.Revert();
+
+			service.Verify(s => s.StopSession(It.Is<Guid>(id => id == context.Next.SessionId)), Times.Once);
+			service.Verify(s => s.Disconnect(), Times.Once);
+			service.Verify(s => s.RunSystemConfigurationUpdate(), Times.Once);
+
+			Assert.AreEqual(OperationResult.Success, result);
+		}
+
+		[TestMethod]
+		public void Revert_MustStopSessionIfNewSessionNotCompletelyStarted()
+		{
+			var sessionId = Guid.NewGuid();
+
+			context.Current.SessionId = Guid.NewGuid();
+			context.Next.SessionId = sessionId;
+
+			PerformNormally();
+
+			context.Current.SessionId = default(Guid);
+			context.Next.SessionId = default(Guid);
+			service.Setup(s => s.StopSession(It.Is<Guid>(id => id == sessionId))).Returns(new CommunicationResult(true)).Callback(() => serviceEvent.Set());
+			service.Setup(s => s.RunSystemConfigurationUpdate()).Returns(new CommunicationResult(true));
+			service.Setup(s => s.Disconnect()).Returns(true);
+
+			var result = sut.Revert();
+
+			service.Verify(s => s.StopSession(It.Is<Guid>(id => id == sessionId)), Times.Once);
+			service.Verify(s => s.StopSession(It.Is<Guid>(id => id == default(Guid))), Times.Never);
+			service.Verify(s => s.Disconnect(), Times.Once);
+
+			Assert.AreEqual(OperationResult.Success, result);
+		}
+
 		private void PerformNormally()
 		{
 			service.SetupGet(s => s.IsConnected).Returns(true);

SafeExamBrowser.Runtime/Operations/ServiceOperation.cs

@@ -12,12 +12,12 @@ using System.Threading;
 using SafeExamBrowser.Communication.Contracts.Hosts;
 using SafeExamBrowser.Communication.Contracts.Proxies;
 using SafeExamBrowser.Configuration.Contracts;
-using SafeExamBrowser.Settings.Service;
 using SafeExamBrowser.Core.Contracts.OperationModel;
 using SafeExamBrowser.Core.Contracts.OperationModel.Events;
 using SafeExamBrowser.I18n.Contracts;
 using SafeExamBrowser.Logging.Contracts;
 using SafeExamBrowser.Runtime.Operations.Events;
+using SafeExamBrowser.Settings.Service;
 using SafeExamBrowser.SystemComponents.Contracts;
 using SafeExamBrowser.UserInterface.Contracts.MessageBox;
 
@@ -28,6 +28,8 @@ namespace SafeExamBrowser.Runtime.Operations
 		private ILogger logger;
 		private IRuntimeHost runtimeHost;
 		private IServiceProxy service;
+		private string serviceEventName;
+		private Guid? sessionId;
 		private int timeout_ms;
 		private IUserInfo userInfo;
 
@@ -54,9 +56,9 @@ namespace SafeExamBrowser.Runtime.Operations
 			logger.Info($"Initializing service...");
 			StatusChanged?.Invoke(TextKey.OperationStatus_InitializeServiceSession);
 
-			var success = TryEstablishConnection();
+			var success = TryInitializeConnection();
 
-			if (service.IsConnected)
+			if (success && service.IsConnected)
 			{
 				success = TryStartSession();
 			}
@@ -69,15 +71,15 @@ namespace SafeExamBrowser.Runtime.Operations
 			logger.Info($"Initializing service...");
 			StatusChanged?.Invoke(TextKey.OperationStatus_InitializeServiceSession);
 
-			var success = false;
+			var success = true;
 
-			if (service.IsConnected)
+			if (service.IsConnected && sessionId.HasValue)
 			{
 				success = TryStopSession();
 			}
-			else
+			else if (!service.IsConnected)
 			{
-				success = TryEstablishConnection();
+				success = TryInitializeConnection();
 			}
 
 			if (success && service.IsConnected)
@@ -97,7 +99,7 @@ namespace SafeExamBrowser.Runtime.Operations
 
 			if (service.IsConnected)
 			{
-				if (Context.Current != null)
+				if (sessionId.HasValue)
 				{
 					success &= TryStopSession(true);
 				}
@@ -108,7 +110,7 @@ namespace SafeExamBrowser.Runtime.Operations
 			return success ? OperationResult.Success : OperationResult.Failed;
 		}
 
-		private bool TryEstablishConnection()
+		private bool TryInitializeConnection()
 		{
 			var mandatory = Context.Next.Settings.Service.Policy == ServicePolicy.Mandatory;
 			var warn = Context.Next.Settings.Service.Policy == ServicePolicy.Warn;
@@ -117,8 +119,7 @@ namespace SafeExamBrowser.Runtime.Operations
 
 			if (success)
 			{
-				service.Ignore = !connected;
+				logger.Info($"The service is {(mandatory ? "mandatory" : "optional")} and {(connected ? "connected." : "not connected.")}");
-				logger.Info($"The service is {(mandatory ? "mandatory" : "optional")} and {(connected ? "connected." : "not connected. All service-related operations will be ignored!")}");
 
 				if (!connected && warn)
 				{
@@ -182,6 +183,8 @@ namespace SafeExamBrowser.Runtime.Operations
 
 				if (started)
 				{
+					sessionId = Context.Next.SessionId;
+					serviceEventName = Context.Next.AppConfig.ServiceEventName;
 					logger.Info("Successfully started new service session.");
 				}
 				else
@@ -203,14 +206,16 @@ namespace SafeExamBrowser.Runtime.Operations
 
 			logger.Info("Stopping current service session...");
 
-			var communication = service.StopSession(Context.Current.SessionId);
+			var communication = service.StopSession(sessionId.Value);
 
 			if (communication.Success)
 			{
-				success = TryWaitForServiceEvent(Context.Current.AppConfig.ServiceEventName);
+				success = TryWaitForServiceEvent(serviceEventName);
 
 				if (success)
 				{
+					sessionId = default(Guid?);
+					serviceEventName = default(string);
 					logger.Info("Successfully stopped service session.");
 				}
 				else