diff --git a/SafeExamBrowser.SystemComponents/Registry/Registry.cs b/SafeExamBrowser.SystemComponents/Registry/Registry.cs
index c1def091..6eacccbe 100644
--- a/SafeExamBrowser.SystemComponents/Registry/Registry.cs
+++ b/SafeExamBrowser.SystemComponents/Registry/Registry.cs
@@ -89,23 +89,23 @@ namespace SafeExamBrowser.SystemComponents.Registry
 			return success;
 		}
 
-		public bool TryGetNames(string key, out IEnumerable<string> names)
+		public bool TryGetNames(string keyName, out IEnumerable<string> names)
 		{
 			names = default;
 
-			if (!TryOpenKey(key, out var keyObj))
+			if (!TryOpenKey(keyName, out var key))
 				return false;
 
 			bool success = true;
-			using (keyObj)
+			using (key)
 			{
 				try
 				{
-					names = keyObj.GetValueNames();
+					names = key.GetValueNames();
 				}
 				catch (Exception e)
 				{
-					logger.Error($"Failed to get registry value names '{key}'!", e);
+					logger.Error($"Failed to get registry value names '{keyName}'!", e);
 					success = false;
 					// persist keyObj dispose operation by finishing using() {}
 				}
@@ -115,23 +115,23 @@ namespace SafeExamBrowser.SystemComponents.Registry
 			return success;
 		}
 
-		public bool TryGetSubKeys(string key, out IEnumerable<string> subKeys)
+		public bool TryGetSubKeys(string keyName, out IEnumerable<string> subKeys)
 		{
 			subKeys = default;
 			
-			if (!TryOpenKey(key, out var keyObj))
+			if (!TryOpenKey(keyName, out var key))
 				return false;
 
 			bool success = true;
-			using (keyObj)
+			using (key)
 			{
 				try
 				{
-					subKeys = keyObj.GetSubKeyNames();
+					subKeys = key.GetSubKeyNames();
 				}
 				catch (Exception e)
 				{
-					logger.Error($"Failed to get registry value names '{key}'!", e);
+					logger.Error($"Failed to get registry value names '{keyName}'!", e);
 					success = false;
 					// persist keyObj dispose operation by finishing using() {}
 				}
@@ -234,25 +234,25 @@ namespace SafeExamBrowser.SystemComponents.Registry
 		/// <summary>
 		/// Tries to open a key and outputs a RegistryKey object. Does not raise Exceptions, but returns false/true.
 		/// </summary>
-		private bool TryOpenKey(string key, out RegistryKey keyObj)
+		private bool TryOpenKey(string keyName, out RegistryKey key)
 		{
-			keyObj = default;
+			key = default;
 
 			try
 			{
-				if (!GetBaseKeyFromKeyName(key, out var hiveObj, out var subHiveKey))
+				if (!GetBaseKeyFromKeyName(keyName, out var hiveObj, out var subHiveKey))
 					return false;
 
-				keyObj = hiveObj.OpenSubKey(subHiveKey);
-				if (keyObj == null)
+				key = hiveObj.OpenSubKey(subHiveKey);
+				if (key == null)
 				{
-					keyObj = default;
+					key = default;
 					return false;
 				}
 			}
 			catch (Exception e)
 			{
-				logger.Error($"Failed to open registry key '{key}'!", e);
+				logger.Error($"Failed to open registry key '{keyName}'!", e);
 				return false;
 			}
 
diff --git a/SafeExamBrowser.SystemComponents/VirtualMachineDetector.cs b/SafeExamBrowser.SystemComponents/VirtualMachineDetector.cs
index 4b1943b3..fc80450a 100644
--- a/SafeExamBrowser.SystemComponents/VirtualMachineDetector.cs
+++ b/SafeExamBrowser.SystemComponents/VirtualMachineDetector.cs
@@ -119,7 +119,7 @@ namespace SafeExamBrowser.SystemComponents
 		/// </summary>
 		private bool IsVirtualRegistryHardwareConfig()
 		{
-			bool isVirtualMachine = false;
+			var isVirtualMachine = false;
 
 			/** 
 			 * scanned registry format:
@@ -135,19 +135,18 @@ namespace SafeExamBrowser.SystemComponents
 			foreach (string configId in hardwareConfigSubkeys)
 			{
 				var hwConfigKey = $"{hwConfigParentKey}\\{configId}";
+				bool didReadKeys = true;
 
 				// collect system values for IsVirtualSystemInfo()
-				bool success = true;
-				success &= registry.TryRead(hwConfigKey, "BIOSVendor", out var biosVendor);
-				success &= registry.TryRead(hwConfigKey, "BIOSVersion", out var biosVersion);
-				success &= registry.TryRead(hwConfigKey, "SystemManufacturer", out var systemManufacturer);
-				success &= registry.TryRead(hwConfigKey, "SystemProductName", out var systemProductName);
-
-				if (!success)
+				didReadKeys &= registry.TryRead(hwConfigKey, "BIOSVendor", out var biosVendor);
+				didReadKeys &= registry.TryRead(hwConfigKey, "BIOSVersion", out var biosVersion);
+				didReadKeys &= registry.TryRead(hwConfigKey, "SystemManufacturer", out var systemManufacturer);
+				didReadKeys &= registry.TryRead(hwConfigKey, "SystemProductName", out var systemProductName);
+				if (!didReadKeys)
 					continue;
 
 				// reconstruct the systemInfo.biosInfo string
-				string biosInfo = $"{(string) biosVendor} {(string) biosVersion}";
+				var biosInfo = $"{(string) biosVendor} {(string) biosVersion}";
 
 				isVirtualMachine |= IsVirtualSystemInfo(biosInfo, (string) systemManufacturer, (string) systemProductName);
 
@@ -174,31 +173,30 @@ namespace SafeExamBrowser.SystemComponents
 		/// </summary>
 		private bool IsVirtualRegistryDeviceCache()
 		{
-			bool isVirtualMachine = false;
+			var isVirtualMachine = false;
 
 			// device cache contains hardware about other devices logged into as well, so lock onto this device in case an innocent VM was logged into.
 			// in the future, try to improve this check somehow since DeviceCache only gives ComputerName
 			var deviceName = System.Environment.GetEnvironmentVariable("COMPUTERNAME");
 
 			// check Windows timeline caches for current hardware config
-			const string deviceCacheParentKey = "HKCU\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\TaskFlow\\DeviceCache";
-			bool has_dc_keys = registry.TryGetSubKeys(deviceCacheParentKey, out var deviceCacheKeys);
+			const string deviceCacheParentKey = "HKEY_CURRENT_USER\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\TaskFlow\\DeviceCache";
+			var hasDeviceCacheKeys = registry.TryGetSubKeys(deviceCacheParentKey, out var deviceCacheKeys);
 
-			if (deviceName != null && has_dc_keys)
+			if (deviceName != null && hasDeviceCacheKeys)
 			{
-				foreach (string cacheId in deviceCacheKeys)
+				foreach (var cacheId in deviceCacheKeys)
 				{
 					var cacheIdKey = $"{deviceCacheParentKey}\\{cacheId}";
+					var didReadKeys = true;
 
-					bool success = true;
-					success &= registry.TryRead(cacheIdKey, "DeviceName", out var cacheDeviceName);
-
-					if (!success || deviceName.ToLower() != ((string) cacheDeviceName).ToLower())
+					didReadKeys &= registry.TryRead(cacheIdKey, "DeviceName", out var cacheDeviceName);
+					if (!didReadKeys || deviceName.ToLower() != ((string) cacheDeviceName).ToLower())
 						continue;
 
-					success &= registry.TryRead(cacheIdKey, "DeviceMake", out var cacheDeviceManufacturer);
-					success &= registry.TryRead(cacheIdKey, "DeviceModel", out var cacheDeviceModel);
-					if (!success)
+					didReadKeys &= registry.TryRead(cacheIdKey, "DeviceMake", out var cacheDeviceManufacturer);
+					didReadKeys &= registry.TryRead(cacheIdKey, "DeviceModel", out var cacheDeviceModel);
+					if (!didReadKeys)
 						continue;
 
 					isVirtualMachine |= IsVirtualSystemInfo("", (string) cacheDeviceManufacturer, (string) cacheDeviceModel);