diff --git a/AMWD.Common.Tests/Extensions/CryptographyHelperExtensionsTests.cs b/AMWD.Common.Tests/Extensions/CryptographyHelperExtensionsTests.cs
index 0863776..4852e6a 100644
--- a/AMWD.Common.Tests/Extensions/CryptographyHelperExtensionsTests.cs
+++ b/AMWD.Common.Tests/Extensions/CryptographyHelperExtensionsTests.cs
@@ -4,6 +4,7 @@ using Microsoft.VisualStudio.TestTools.UnitTesting;
 namespace AMWD.Common.Tests.Extensions
 {
 	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public class CryptographyHelperExtensionsTests
 	{
 		[TestMethod]
diff --git a/AMWD.Common.Tests/Extensions/DateTimeExtensionsTests.cs b/AMWD.Common.Tests/Extensions/DateTimeExtensionsTests.cs
index ad9878a..29531df 100644
--- a/AMWD.Common.Tests/Extensions/DateTimeExtensionsTests.cs
+++ b/AMWD.Common.Tests/Extensions/DateTimeExtensionsTests.cs
@@ -5,6 +5,7 @@ using Microsoft.VisualStudio.TestTools.UnitTesting;
 namespace AMWD.Common.Tests.Extensions
 {
 	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public class DateTimeExtensionsTests
 	{
 		[TestMethod]
diff --git a/AMWD.Common.Tests/Extensions/EnumExtensionsTests.cs b/AMWD.Common.Tests/Extensions/EnumExtensionsTests.cs
index 62f91bc..0689300 100644
--- a/AMWD.Common.Tests/Extensions/EnumExtensionsTests.cs
+++ b/AMWD.Common.Tests/Extensions/EnumExtensionsTests.cs
@@ -7,6 +7,7 @@ using DescriptionAttribute = System.ComponentModel.DescriptionAttribute;
 namespace AMWD.Common.Tests.Extensions
 {
 	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public class EnumExtensionsTests
 	{
 		[TestMethod]
@@ -93,6 +94,19 @@ namespace AMWD.Common.Tests.Extensions
 			Assert.AreEqual(enumWithoutDescripton.ToString(), noDescription);
 		}
 
+		[TestMethod]
+		public void ShouldReturnEmptyListOnNotDefinedEnumValue()
+		{
+			// arrange
+			var notDefinedEnum = (TestEnum)10;
+
+			// act
+			var list = notDefinedEnum.GetAttributes<DescriptionAttribute>();
+
+			// assert
+			Assert.IsFalse(list.Any());
+		}
+
 		internal enum TestEnum
 		{
 			[CustomMultiple("nix")]
diff --git a/AMWD.Common.Tests/Extensions/ExceptionExtensionsTests.cs b/AMWD.Common.Tests/Extensions/ExceptionExtensionsTests.cs
new file mode 100644
index 0000000..8e691dc
--- /dev/null
+++ b/AMWD.Common.Tests/Extensions/ExceptionExtensionsTests.cs
@@ -0,0 +1,75 @@
+using System;
+using System.Collections.Generic;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace AMWD.Common.Tests.Extensions
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class ExceptionExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldReturnExceptionMessage()
+		{
+			// arrange
+			var exception = new Exception("This is a message.");
+
+			// act
+			string message = exception.GetMessage();
+
+			// assert
+			Assert.AreEqual(exception.Message, message);
+		}
+
+		[TestMethod]
+		public void ShouldReturnInnerExceptionMessage()
+		{
+			// arrange
+			var innerException = new Exception("Message from the inner side.");
+			var outerException = new Exception("Message from the outer side.", innerException);
+
+			// act
+			string message = outerException.GetMessage();
+
+			// assert
+			Assert.AreEqual(innerException.Message, message);
+		}
+
+		[TestMethod]
+		public void ShouldReturnRecursiveExceptionMessageFoInnerException()
+		{
+			// arrange
+			var innerException = new Exception("Message from the inner side.");
+			var outerException = new Exception("Message from the outer side. See the inner exception for details.", innerException);
+			string expectedMessage = $"Message from the outer side. Message from the inner side.";
+
+			// act
+			string message = outerException.GetRecursiveMessage();
+
+			// assert
+			Assert.AreEqual(expectedMessage, message);
+		}
+
+		[TestMethod]
+		public void ShouldReturnRecursiveExceptionMessageFoInnerExceptions()
+		{
+			// arrange
+			var innerExceptions = new List<Exception>
+			{
+				new Exception("Inner Exception 1."),
+				new Exception("Inner Exception 2. See the inner exception for details.", new Exception("Inner Exception of Exception 2.")),
+				new Exception("Inner Exception 3."),
+				new Exception("Inner Exception 4."),
+				new Exception("Inner Exception 5.")
+			};
+			var aggregateException = new AggregateException("Lots of exceptions.", innerExceptions);
+			string expectedMessage = "Inner Exception 1. Inner Exception 2. Inner Exception of Exception 2. Inner Exception 3.";
+
+			// act
+			string message = aggregateException.GetRecursiveMessage();
+
+			// assert
+			Assert.AreEqual(expectedMessage, message);
+		}
+	}
+}
diff --git a/AMWD.Common.Tests/Extensions/JsonExtensionsTests.cs b/AMWD.Common.Tests/Extensions/JsonExtensionsTests.cs
index ca36604..ef2af2f 100644
--- a/AMWD.Common.Tests/Extensions/JsonExtensionsTests.cs
+++ b/AMWD.Common.Tests/Extensions/JsonExtensionsTests.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections;
 using AMWD.Common.Tests.Utils;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using Newtonsoft.Json;
@@ -7,6 +8,7 @@ using Newtonsoft.Json.Linq;
 namespace AMWD.Common.Tests.Extensions
 {
 	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public class JsonExtensionsTests
 	{
 		[TestMethod]
@@ -303,5 +305,37 @@ namespace AMWD.Common.Tests.Extensions
 			Assert.AreEqual("Well Done", notExistingOnSubLevel);
 			Assert.AreEqual(13, notExistingLevel);
 		}
+
+		[TestMethod]
+		public void ShouldReturnNull()
+		{
+			// arrange
+			object obj = null;
+			IEnumerable list = null;
+			JObject jObj = null;
+
+			// act
+			var objTest = obj.ConvertToJObject();
+			var listTest = list.ConvertToJArray();
+			object getTest = jObj.GetValue<object>("Nothing");
+
+			// assert
+			Assert.IsNull(objTest);
+			Assert.IsNull(listTest);
+			Assert.IsNull(getTest);
+		}
+
+		[TestMethod]
+		public void ShouldHandleSerializationError()
+		{
+			// arrange
+			var obj = new JsonErrorClass();
+
+			// act
+			string json = obj.SerializeJson();
+
+			// assert
+			Assert.AreEqual("{}", json);
+		}
 	}
 }
diff --git a/AMWD.Common.Tests/Extensions/ReaderWriterLockSlimExtensionsTests.cs b/AMWD.Common.Tests/Extensions/ReaderWriterLockSlimExtensionsTests.cs
index ca839ce..12bea95 100644
--- a/AMWD.Common.Tests/Extensions/ReaderWriterLockSlimExtensionsTests.cs
+++ b/AMWD.Common.Tests/Extensions/ReaderWriterLockSlimExtensionsTests.cs
@@ -1,9 +1,12 @@
+using System;
 using System.Threading;
+using System.Threading.Tasks;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 
 namespace AMWD.Common.Tests.Extensions
 {
 	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public class ReaderWriterLockSlimExtensionsTests
 	{
 		[TestMethod]
@@ -38,6 +41,39 @@ namespace AMWD.Common.Tests.Extensions
 			Assert.IsFalse(rwLock.IsWriteLockHeld);
 		}
 
+		[TestMethod]
+		public void ShouldAllowWriteLockAfterUpgradableReadLock()
+		{
+			// arrange
+			var rwLockUsing = new ReaderWriterLockSlim();
+			var rwLockClassic = new ReaderWriterLockSlim();
+
+			// act
+			using var disposableReadUsing = rwLockUsing.GetUpgradeableReadLock();
+			using (rwLockUsing.GetWriteLock())
+			{
+				// assert
+				Assert.IsTrue(rwLockUsing.IsUpgradeableReadLockHeld);
+				Assert.IsTrue(rwLockUsing.IsWriteLockHeld);
+			}
+			// assert
+			Assert.IsTrue(rwLockUsing.IsUpgradeableReadLockHeld);
+			Assert.IsFalse(rwLockUsing.IsWriteLockHeld);
+
+			// act
+			using (rwLockClassic.GetUpgradeableReadLock())
+			{
+				rwLockClassic.EnterWriteLock();
+
+				// assert
+				Assert.IsTrue(rwLockClassic.IsUpgradeableReadLockHeld);
+				Assert.IsTrue(rwLockClassic.IsWriteLockHeld);
+			}
+			// assert
+			Assert.IsFalse(rwLockClassic.IsUpgradeableReadLockHeld);
+			Assert.IsFalse(rwLockClassic.IsWriteLockHeld);
+		}
+
 		[TestMethod]
 		public void ShouldEnterWriteLock()
 		{
@@ -85,14 +121,101 @@ namespace AMWD.Common.Tests.Extensions
 
 			// act
 			using var disposableRead = rwLock.GetUpgradeableReadLock();
-			using var disposaleWrite = rwLock.GetWriteLock();
+			using var disposableWrite = rwLock.GetWriteLock();
 
 			// assert
 			Assert.IsNotNull(disposableRead);
-			Assert.IsNotNull(disposaleWrite);
+			Assert.IsNotNull(disposableWrite);
 			Assert.IsFalse(rwLock.IsReadLockHeld);
 			Assert.IsTrue(rwLock.IsUpgradeableReadLockHeld);
 			Assert.IsTrue(rwLock.IsWriteLockHeld);
 		}
+
+		[TestMethod]
+		public void ShouldGetTimeoutOnReadLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+			bool isTimeout = false;
+
+			// act
+			using var disposableRead = rwLock.GetWriteLock();
+			var awaitableTask = Task.Run(() =>
+			{
+				try
+				{
+					using var disposableRead = rwLock.GetReadLock(10);
+					Assert.Fail();
+				}
+				catch (TimeoutException)
+				{
+					isTimeout = true;
+				}
+				catch (Exception)
+				{ /* keep it quiet */ }
+			});
+			Task.WaitAll(awaitableTask);
+
+			// assert
+			Assert.IsTrue(isTimeout);
+		}
+
+		[TestMethod]
+		public void ShouldGetTimeoutOnUpgradeableReadLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+			bool isTimeout = false;
+
+			// act
+			using var disposableRead = rwLock.GetWriteLock();
+			var awaitableTask = Task.Run(() =>
+			{
+				try
+				{
+					using var disposableRead = rwLock.GetUpgradeableReadLock(10);
+					Assert.Fail();
+				}
+				catch (TimeoutException)
+				{
+					isTimeout = true;
+				}
+				catch (Exception)
+				{ /* keep it quiet */ }
+			});
+			Task.WaitAll(awaitableTask);
+
+			// assert
+			Assert.IsTrue(isTimeout);
+		}
+
+		[TestMethod]
+		public void ShouldGetTimeoutOnWriteLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+			bool isTimeout = false;
+
+			// act
+			using var disposableRead = rwLock.GetReadLock();
+			var awaitableTask = Task.Run(() =>
+			{
+				try
+				{
+					using var disposableRead = rwLock.GetWriteLock(10);
+					Assert.Fail();
+				}
+				catch (TimeoutException)
+				{
+					isTimeout = true;
+				}
+				catch (Exception)
+				{ /* keep it quiet */ }
+			});
+			Task.WaitAll(awaitableTask);
+
+			// assert
+			Assert.IsTrue(isTimeout);
+		}
 	}
 }
diff --git a/AMWD.Common.Tests/Extensions/StringExtensionsTests.cs b/AMWD.Common.Tests/Extensions/StringExtensionsTests.cs
index 0770ef2..162290c 100644
--- a/AMWD.Common.Tests/Extensions/StringExtensionsTests.cs
+++ b/AMWD.Common.Tests/Extensions/StringExtensionsTests.cs
@@ -7,6 +7,7 @@ using Microsoft.VisualStudio.TestTools.UnitTesting;
 namespace AMWD.Common.Tests.Extensions
 {
 	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public class StringExtensionsTests
 	{
 		[TestMethod]
@@ -132,10 +133,12 @@ namespace AMWD.Common.Tests.Extensions
 			string plain = "Hello";
 
 			// act
-			string hex = plain.HexEncode(Encoding.UTF8);
+			string hex1 = plain.HexEncode();
+			string hex2 = plain.HexEncode(Encoding.Default);
 
 			// assert
-			Assert.AreEqual("48656c6c6f", hex);
+			Assert.AreEqual("48656c6c6f", hex1);
+			Assert.AreEqual("48656c6c6f", hex2);
 		}
 
 		[TestMethod]
@@ -145,10 +148,12 @@ namespace AMWD.Common.Tests.Extensions
 			string hex = "48656c6c6f";
 
 			// act
-			string plain = hex.HexDecode(Encoding.UTF8);
+			string plain1 = hex.HexDecode();
+			string plain2 = hex.HexDecode(Encoding.Default);
 
 			// assert
-			Assert.AreEqual("Hello", plain);
+			Assert.AreEqual("Hello", plain1);
+			Assert.AreEqual("Hello", plain2);
 		}
 
 		[TestMethod]
@@ -158,10 +163,12 @@ namespace AMWD.Common.Tests.Extensions
 			string plain = "Hello";
 
 			// act
-			string base64 = plain.Base64Encode(Encoding.UTF8);
+			string base641 = plain.Base64Encode();
+			string base642 = plain.Base64Encode(Encoding.Default);
 
 			// assert
-			Assert.AreEqual("SGVsbG8=", base64);
+			Assert.AreEqual("SGVsbG8=", base641);
+			Assert.AreEqual("SGVsbG8=", base642);
 		}
 
 		[TestMethod]
@@ -171,10 +178,12 @@ namespace AMWD.Common.Tests.Extensions
 			string base64 = "SGVsbG8=";
 
 			// act
-			string plain = base64.Base64Decode(Encoding.UTF8);
+			string plain1 = base64.Base64Decode();
+			string plain2 = base64.Base64Decode(Encoding.Default);
 
 			// assert
-			Assert.AreEqual("Hello", plain);
+			Assert.AreEqual("Hello", plain1);
+			Assert.AreEqual("Hello", plain2);
 		}
 
 		[TestMethod]
@@ -255,18 +264,21 @@ namespace AMWD.Common.Tests.Extensions
 			string validEmailWithTag = "test+tag@not.exists";
 			string invalidEmailWithoutTag = "<Test Account> test@gmail.com";
 			string invalidEmailWithTag = "<Test Account> test+tag@not.exists";
+			string nullStr = null;
 
 			// act
 			bool validWithoutTag = validEmailWithoutTag.IsValidEmailAddress(checkRecordExists: false);
 			bool validWithTag = validEmailWithTag.IsValidEmailAddress(checkRecordExists: false);
 			bool invalidWithoutTag = !invalidEmailWithoutTag.IsValidEmailAddress(checkRecordExists: false);
 			bool invalidWithTag = !invalidEmailWithTag.IsValidEmailAddress(checkRecordExists: false);
+			bool nullTest = nullStr.IsValidEmailAddress(checkRecordExists: false);
 
 			// assert
 			Assert.IsTrue(validWithoutTag);
 			Assert.IsTrue(validWithTag);
 			Assert.IsTrue(invalidWithoutTag);
 			Assert.IsTrue(invalidWithTag);
+			Assert.IsFalse(nullTest);
 		}
 
 		[TestMethod]
@@ -301,5 +313,25 @@ namespace AMWD.Common.Tests.Extensions
 			Assert.IsTrue(valid);
 			Assert.IsTrue(invalid);
 		}
+
+		[TestMethod]
+		public void ShouldWorkWithNullOrEmptyString()
+		{
+			// arrange
+			string nullStr = null;
+			string emptyStr = "";
+
+			// act
+			string hexEncodeNull = nullStr.HexEncode();
+			string hexEncodeEmpty = emptyStr.HexEncode();
+			string hexDecodeNull = nullStr.HexDecode();
+			string hexDecodeEmpty = emptyStr.HexDecode();
+
+			// assert
+			Assert.IsNull(hexEncodeNull);
+			Assert.AreEqual("", hexEncodeEmpty);
+			Assert.IsNull(hexDecodeNull);
+			Assert.AreEqual("", hexDecodeEmpty);
+		}
 	}
 }
diff --git a/AMWD.Common.Tests/Utilities/CryptographyHelperTests.cs b/AMWD.Common.Tests/Utilities/CryptographyHelperTests.cs
index 347cdb3..a702648 100644
--- a/AMWD.Common.Tests/Utilities/CryptographyHelperTests.cs
+++ b/AMWD.Common.Tests/Utilities/CryptographyHelperTests.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Diagnostics;
 using System.IO;
+using System.Reflection;
 using System.Security.Cryptography;
 using System.Text.RegularExpressions;
 using AMWD.Common.Tests.Utils;
@@ -9,6 +10,7 @@ using Microsoft.VisualStudio.TestTools.UnitTesting;
 namespace AMWD.Common.Tests.Utilities
 {
 	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public class CryptographyHelperTests
 	{
 		private string keyFile;
@@ -430,10 +432,15 @@ namespace AMWD.Common.Tests.Utilities
 			string str2 = "Hello World!";
 			string str3 = "Hallo World!";
 			string str4 = "Hello World?";
+			string nullStr = null;
+			string strLen = "Hello World";
 
 			var sw = new Stopwatch();
 
 			// act
+			bool nullCompare = CryptographyHelper.SecureEquals(nullStr, str1);
+			bool lenCompare = CryptographyHelper.SecureEquals(strLen, str1);
+
 			sw.Start();
 			bool compare1 = CryptographyHelper.SecureEquals(str1, str2);
 			long time1 = sw.ElapsedMilliseconds;
@@ -446,10 +453,12 @@ namespace AMWD.Common.Tests.Utilities
 			sw.Stop();
 
 			// assert
+			Assert.IsFalse(nullCompare);
+			Assert.IsFalse(lenCompare);
 			Assert.IsTrue(compare1);
 			Assert.IsFalse(compare2);
 			Assert.IsFalse(compare3);
-			// max. time delta: 2 ticks per character
+
 			Assert.AreEqual(time1, time2);
 			Assert.AreEqual(time1, time3);
 			Assert.AreEqual(time2, time3);
@@ -463,6 +472,8 @@ namespace AMWD.Common.Tests.Utilities
 			byte[] bytes2 = new byte[bytes1.Length];
 			byte[] bytes3 = new byte[bytes1.Length];
 			byte[] bytes4 = new byte[bytes1.Length];
+			byte[] nullBytes = null;
+			byte[] lenBytes = new byte[bytes1.Length + 1];
 
 			Array.Copy(bytes1, bytes2, bytes1.Length);
 			Array.Copy(bytes1, bytes3, bytes1.Length);
@@ -474,6 +485,9 @@ namespace AMWD.Common.Tests.Utilities
 			var sw = new Stopwatch();
 
 			// act
+			bool nullCompare = CryptographyHelper.SecureEquals(nullBytes, bytes1);
+			bool lenCompare = CryptographyHelper.SecureEquals(lenBytes, bytes1);
+
 			sw.Start();
 			bool compare1 = CryptographyHelper.SecureEquals(bytes1, bytes2);
 			long time1 = sw.ElapsedMilliseconds;
@@ -486,10 +500,12 @@ namespace AMWD.Common.Tests.Utilities
 			sw.Stop();
 
 			// assert
+			Assert.IsFalse(nullCompare);
+			Assert.IsFalse(lenCompare);
 			Assert.IsTrue(compare1);
 			Assert.IsFalse(compare2);
 			Assert.IsFalse(compare3);
-			// max. time delta: 2 ticks per byte
+
 			Assert.AreEqual(time1, time2);
 			Assert.AreEqual(time1, time3);
 			Assert.AreEqual(time2, time3);
@@ -501,6 +517,28 @@ namespace AMWD.Common.Tests.Utilities
 
 		#region Instance
 
+		[TestMethod]
+		public void ShouldCreateDefaultFile()
+		{
+			// arrange
+			string executingAssemblyDir = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
+			string filePath = Path.Combine(executingAssemblyDir, "crypto.key");
+
+			// act
+			bool fileExistsBefore = File.Exists(filePath);
+			var helper = new CryptographyHelper();
+			bool fileExistsAfter = File.Exists(filePath);
+			string content = fileExistsAfter ? File.ReadAllText(filePath) : null;
+			File.Delete(filePath);
+
+			// assert
+			Assert.IsFalse(fileExistsBefore);
+			Assert.IsNotNull(helper);
+			Assert.IsTrue(fileExistsAfter);
+			Assert.IsTrue(!string.IsNullOrWhiteSpace(content));
+		}
+
+
 		[TestMethod]
 		public void ShouldEncryptAesUsingKeyFile()
 		{
diff --git a/AMWD.Common.Tests/Utilities/DelayedTaskTests.cs b/AMWD.Common.Tests/Utilities/DelayedTaskTests.cs
index ad61841..9cdce47 100644
--- a/AMWD.Common.Tests/Utilities/DelayedTaskTests.cs
+++ b/AMWD.Common.Tests/Utilities/DelayedTaskTests.cs
@@ -8,6 +8,7 @@ using Microsoft.VisualStudio.TestTools.UnitTesting;
 namespace AMWD.Common.Tests.Utilities
 {
 	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public class DelayedTaskTests
 	{
 		// TODO
diff --git a/AMWD.Common.Tests/Utils/JsonTestClass.cs b/AMWD.Common.Tests/Utils/JsonTestClass.cs
index 9d1ed3b..2bf41d2 100644
--- a/AMWD.Common.Tests/Utils/JsonTestClass.cs
+++ b/AMWD.Common.Tests/Utils/JsonTestClass.cs
@@ -29,4 +29,22 @@ namespace AMWD.Common.Tests.Utils
 
 		public string StringValue { get; set; } = "Foo-Bar";
 	}
+
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	internal class JsonErrorClass
+	{
+		private int? number;
+
+		public int Number
+		{
+			get
+			{
+				if (number.HasValue)
+					return number.Value;
+
+				throw new Exception("Null value");
+			}
+			set { number = value; }
+		}
+	}
 }
diff --git a/AMWD.Common/Extensions/ExceptionExtensions.cs b/AMWD.Common/Extensions/ExceptionExtensions.cs
index bece785..d1a0aa3 100644
--- a/AMWD.Common/Extensions/ExceptionExtensions.cs
+++ b/AMWD.Common/Extensions/ExceptionExtensions.cs
@@ -5,7 +5,6 @@ namespace System
 	/// <summary>
 	/// Provides extension methods for exceptions.
 	/// </summary>
-	[Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public static class ExceptionExtensions
 	{
 		/// <summary>
diff --git a/AMWD.Common/Extensions/ReaderWriterLockSlimExtensions.cs b/AMWD.Common/Extensions/ReaderWriterLockSlimExtensions.cs
index 40de6cb..6af910e 100644
--- a/AMWD.Common/Extensions/ReaderWriterLockSlimExtensions.cs
+++ b/AMWD.Common/Extensions/ReaderWriterLockSlimExtensions.cs
@@ -1,6 +1,4 @@
-//[assembly: System.Runtime.CompilerServices.InternalsVisibleTo("AMWD.Common.Tests")]
-
-namespace System.Threading
+namespace System.Threading
 {
 	/// <summary>
 	/// Provides extension methods for the <see cref="ReaderWriterLockSlim"/>.