diff --git a/src/NuGetGallery/App_Start/AppActivator.cs b/src/NuGetGallery/App_Start/AppActivator.cs
index bf113702af..0e3d9de880 100644
--- a/src/NuGetGallery/App_Start/AppActivator.cs
+++ b/src/NuGetGallery/App_Start/AppActivator.cs
@@ -62,7 +62,7 @@ public static void PostStart()
         {
             if (!OwinStartup.HasRun)
             {
-                throw new NullReferenceException("The OwinStartup module did not run. Make sure the application runs in an OWIN pipeline and Microsoft.Owin.Host.SystemWeb.dll is in the bin directory.");
+                throw new AppActivatorException("The OwinStartup module did not run. Make sure the application runs in an OWIN pipeline and Microsoft.Owin.Host.SystemWeb.dll is in the bin directory.");
             }
 
             // Get configuration from the kernel
diff --git a/src/NuGetGallery/NuGetGallery.csproj b/src/NuGetGallery/NuGetGallery.csproj
index 840ebd2761..803fb731bf 100644
--- a/src/NuGetGallery/NuGetGallery.csproj
+++ b/src/NuGetGallery/NuGetGallery.csproj
@@ -1057,6 +1057,7 @@
     <Content Include="Content\Logos\dnf.png" />
     <Content Include="Scripts\jquery-1.11.0.js" />
     <Content Include="Scripts\jquery-1.11.0.min.js" />
+    <Compile Include="Services\AppActivatorException.cs" />
     <Compile Include="Services\ConfirmOwnershipResult.cs" />
     <Compile Include="Services\CuratedFeedService.cs" />
     <Compile Include="Services\ICuratedFeedService.cs" />
diff --git a/src/NuGetGallery/Services/AppActivatorException.cs b/src/NuGetGallery/Services/AppActivatorException.cs
new file mode 100644
index 0000000000..ecac77eab2
--- /dev/null
+++ b/src/NuGetGallery/Services/AppActivatorException.cs
@@ -0,0 +1,24 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Runtime.Serialization;
+
+namespace NuGetGallery
+{
+    /// <summary>
+    /// Exception thrown when application startup fails.
+    /// </summary>
+    [Serializable]
+    public class AppActivatorException : Exception
+    {
+        public AppActivatorException() { }
+        public AppActivatorException(string message) : base(message) { }
+        public AppActivatorException(string message, Exception inner) : base(message, inner) { }
+        protected AppActivatorException(
+            SerializationInfo info,
+            StreamingContext context)
+            : base(info, context)
+        { }
+    }
+}
\ No newline at end of file
diff --git a/src/NuGetGallery/Services/StatisticsReportNotFoundException.cs b/src/NuGetGallery/Services/StatisticsReportNotFoundException.cs
index 27e5dd799d..0d58ac3763 100644
--- a/src/NuGetGallery/Services/StatisticsReportNotFoundException.cs
+++ b/src/NuGetGallery/Services/StatisticsReportNotFoundException.cs
@@ -1,9 +1,8 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
 using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Web;
+using System.Runtime.Serialization;
 
 namespace NuGetGallery
 {
@@ -17,8 +16,8 @@ public class StatisticsReportNotFoundException : Exception
         public StatisticsReportNotFoundException(string message) : base(message) { }
         public StatisticsReportNotFoundException(string message, Exception inner) : base(message, inner) { }
         protected StatisticsReportNotFoundException(
-          System.Runtime.Serialization.SerializationInfo info,
-          System.Runtime.Serialization.StreamingContext context)
+          SerializationInfo info,
+          StreamingContext context)
             : base(info, context) { }
     }
 }
\ No newline at end of file