diff --git a/NucuCar.Domain.Telemetry/NucuCar.Domain.Telemetry.csproj b/NucuCar.Domain.Telemetry/NucuCar.Domain.Telemetry.csproj
index 9347bd7..7f26de5 100644
--- a/NucuCar.Domain.Telemetry/NucuCar.Domain.Telemetry.csproj
+++ b/NucuCar.Domain.Telemetry/NucuCar.Domain.Telemetry.csproj
@@ -6,7 +6,6 @@
     </PropertyGroup>
 
     <ItemGroup>
-      <ProjectReference Include="..\NucuCar.Common\NucuCar.Common.csproj" />
       <ProjectReference Include="..\NucuCar.Domain\NucuCar.Domain.csproj" />
     </ItemGroup>
 
diff --git a/NucuCar.UnitTests/NucuCar.Domain.Tests/ConnectionStringParserTest.cs b/NucuCar.UnitTests/NucuCar.Domain.Tests/ConnectionStringParserTest.cs
index b4dde39..3e98814 100644
--- a/NucuCar.UnitTests/NucuCar.Domain.Tests/ConnectionStringParserTest.cs
+++ b/NucuCar.UnitTests/NucuCar.Domain.Tests/ConnectionStringParserTest.cs
@@ -3,7 +3,7 @@ using System.Collections.Generic;
 using NucuCar.Domain.Utilities;
 using Xunit;
 
-namespace NucuCar.UnitTests.NucuCar.Common.Tests
+namespace NucuCar.UnitTests.NucuCar.Domain.Tests
 {
     public class ConnectionStringParserTest
     {
diff --git a/NucuCar.UnitTests/NucuCar.Domain.Tests/GuardTest.cs b/NucuCar.UnitTests/NucuCar.Domain.Tests/GuardTest.cs
new file mode 100644
index 0000000..bc65ad2
--- /dev/null
+++ b/NucuCar.UnitTests/NucuCar.Domain.Tests/GuardTest.cs
@@ -0,0 +1,40 @@
+using System;
+using NucuCar.Domain.Utilities;
+using Xunit;
+
+namespace NucuCar.UnitTests.NucuCar.Domain.Tests
+{
+    public class GuardTest
+    {
+        /// <summary>
+        /// Ensure that an exception is thrown when the argument is null or whitespace,
+        /// and no exception is raised when the argument is non-null.
+        /// </summary>
+        [Fact]
+        private void Test_GuardArgumentNotNullOrWhitespace()
+        {
+            Assert.Throws<ArgumentNullException>(() =>
+            {
+                Guard.ArgumentNotNullOrWhiteSpace("null", null);
+            });
+            Assert.Throws<ArgumentNullException>(() =>
+            {
+                Guard.ArgumentNotNullOrWhiteSpace("whitespace", "");
+            });
+            Guard.ArgumentNotNullOrWhiteSpace("string", "string");
+        }
+
+        /// <summary>
+        /// Ensure that an exception is thrown when argument is null. Otherwise no exception should be thrown.
+        /// </summary>
+        [Fact]
+        private void Test_GuardArgumentNotNull()
+        {
+            Assert.Throws<ArgumentNullException>(() =>
+            {
+                Guard.ArgumentNotNull("null", null);
+            });
+            Guard.ArgumentNotNull("object", new string("asd"));
+        }
+    }
+}
\ No newline at end of file
diff --git a/NucuCar.sln.DotSettings.user b/NucuCar.sln.DotSettings.user
index be70b0e..1046fae 100644
--- a/NucuCar.sln.DotSettings.user
+++ b/NucuCar.sln.DotSettings.user
@@ -23,6 +23,6 @@
 &lt;/SessionState&gt;</s:String>
 	<s:String x:Key="/Default/Environment/UnitTesting/UnitTestSessionStore/Sessions/=e8af539e_002D0b50_002D476d_002Daa84_002D80fbff5a748b/@EntryIndexedValue">&lt;SessionState ContinuousTestingMode="0" Name="Test_PublishAsync_OK" xmlns="urn:schemas-jetbrains-com:jetbrains-ut-session"&gt;&#xD;
   &lt;TestAncestor&gt;&#xD;
-    &lt;TestId&gt;xUnit::C6F07921-1052-4945-911E-F328A622F229::.NETCoreApp,Version=v3.1::NucuCar.UnitTests.NucuCar.Telemetry.Tests.TelemetryPublisherFirestoreTest.Test_PublishAsync_OK&lt;/TestId&gt;&#xD;
+    &lt;TestId&gt;xUnit::C6F07921-1052-4945-911E-F328A622F229::.NETCoreApp,Version=v3.1::NucuCar.UnitTests.NucuCar.Domain.Tests.GuardTest&lt;/TestId&gt;&#xD;
   &lt;/TestAncestor&gt;&#xD;
 &lt;/SessionState&gt;</s:String></wpf:ResourceDictionary>
\ No newline at end of file