diff --git a/src/WireMock.Net/Matchers/SimMetricsMatcher.cs b/src/WireMock.Net/Matchers/SimMetricsMatcher.cs
index db49d248..81789f48 100644
--- a/src/WireMock.Net/Matchers/SimMetricsMatcher.cs
+++ b/src/WireMock.Net/Matchers/SimMetricsMatcher.cs
@@ -32,7 +32,7 @@ namespace WireMock.Matchers
         /// <param name="simMetricType">The SimMetric Type</param>
         public SimMetricsMatcher([NotNull] string[] patterns, SimMetricType simMetricType = SimMetricType.Levenstein)
         {
-            Check.NotEmpty(patterns, nameof(patterns));
+            Check.NotNullOrEmpty(patterns, nameof(patterns));
 
             _patterns = patterns;
             _simMetricType = simMetricType;
diff --git a/src/WireMock.Net/Owin/AspNetCoreSelfHost.cs b/src/WireMock.Net/Owin/AspNetCoreSelfHost.cs
index 130b4e72..d3f500d5 100644
--- a/src/WireMock.Net/Owin/AspNetCoreSelfHost.cs
+++ b/src/WireMock.Net/Owin/AspNetCoreSelfHost.cs
@@ -31,7 +31,7 @@ namespace WireMock.Owin
         public AspNetCoreSelfHost([NotNull] WireMockMiddlewareOptions options, [NotNull] params string[] uriPrefixes)
         {
             Check.NotNull(options, nameof(options));
-            Check.NotEmpty(uriPrefixes, nameof(uriPrefixes));
+            Check.NotNullOrEmpty(uriPrefixes, nameof(uriPrefixes));
 
             foreach (string uriPrefix in uriPrefixes)
             {
@@ -51,8 +51,11 @@ namespace WireMock.Owin
                 .Configure(appBuilder =>
                 {
                     appBuilder.UseMiddleware<GlobalExceptionMiddleware>();
+
                     _options.PreWireMockMiddlewareInit?.Invoke(appBuilder);
+
                     appBuilder.UseMiddleware<WireMockMiddleware>(_options);
+
                     _options.PostWireMockMiddlewareInit?.Invoke(appBuilder);
                 })
                 .UseKestrel(options =>
diff --git a/src/WireMock.Net/Owin/OwinSelfHost.cs b/src/WireMock.Net/Owin/OwinSelfHost.cs
index 2f780b80..81231578 100644
--- a/src/WireMock.Net/Owin/OwinSelfHost.cs
+++ b/src/WireMock.Net/Owin/OwinSelfHost.cs
@@ -19,7 +19,7 @@ namespace WireMock.Owin
         public OwinSelfHost([NotNull] WireMockMiddlewareOptions options, [NotNull] params string[] uriPrefixes)
         {
             Check.NotNull(options, nameof(options));
-            Check.NotEmpty(uriPrefixes, nameof(uriPrefixes));
+            Check.NotNullOrEmpty(uriPrefixes, nameof(uriPrefixes));
 
             foreach (string uriPrefix in uriPrefixes)
             {
diff --git a/src/WireMock.Net/RequestBuilders/Request.cs b/src/WireMock.Net/RequestBuilders/Request.cs
index 090d3336..b65bdee4 100644
--- a/src/WireMock.Net/RequestBuilders/Request.cs
+++ b/src/WireMock.Net/RequestBuilders/Request.cs
@@ -61,7 +61,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithClientIP(params IMatcher[] matchers)
         {
-            Check.NotEmpty(matchers, nameof(matchers));
+            Check.NotNullOrEmpty(matchers, nameof(matchers));
 
             _requestMatchers.Add(new RequestMessageClientIPMatcher(matchers));
             return this;
@@ -74,7 +74,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithClientIP(params string[] clientIPs)
         {
-            Check.NotEmpty(clientIPs, nameof(clientIPs));
+            Check.NotNullOrEmpty(clientIPs, nameof(clientIPs));
 
             _requestMatchers.Add(new RequestMessageClientIPMatcher(clientIPs));
             return this;
@@ -87,7 +87,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithClientIP(params Func<string, bool>[] funcs)
         {
-            Check.NotEmpty(funcs, nameof(funcs));
+            Check.NotNullOrEmpty(funcs, nameof(funcs));
 
             _requestMatchers.Add(new RequestMessageClientIPMatcher(funcs));
             return this;
@@ -100,7 +100,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithPath(params IMatcher[] matchers)
         {
-            Check.NotEmpty(matchers, nameof(matchers));
+            Check.NotNullOrEmpty(matchers, nameof(matchers));
 
             _requestMatchers.Add(new RequestMessagePathMatcher(matchers));
             return this;
@@ -113,7 +113,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithPath(params string[] paths)
         {
-            Check.NotEmpty(paths, nameof(paths));
+            Check.NotNullOrEmpty(paths, nameof(paths));
 
             _requestMatchers.Add(new RequestMessagePathMatcher(paths));
             return this;
@@ -126,7 +126,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithPath(params Func<string, bool>[] funcs)
         {
-            Check.NotEmpty(funcs, nameof(funcs));
+            Check.NotNullOrEmpty(funcs, nameof(funcs));
 
             _requestMatchers.Add(new RequestMessagePathMatcher(funcs));
             return this;
@@ -139,7 +139,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithUrl(params IMatcher[] matchers)
         {
-            Check.NotEmpty(matchers, nameof(matchers));
+            Check.NotNullOrEmpty(matchers, nameof(matchers));
 
             _requestMatchers.Add(new RequestMessageUrlMatcher(matchers));
             return this;
@@ -152,7 +152,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithUrl(params string[] urls)
         {
-            Check.NotEmpty(urls, nameof(urls));
+            Check.NotNullOrEmpty(urls, nameof(urls));
 
             _requestMatchers.Add(new RequestMessageUrlMatcher(urls));
             return this;
@@ -165,7 +165,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithUrl(params Func<string, bool>[] funcs)
         {
-            Check.NotEmpty(funcs, nameof(funcs));
+            Check.NotNullOrEmpty(funcs, nameof(funcs));
 
             _requestMatchers.Add(new RequestMessageUrlMatcher(funcs));
             return this;
@@ -228,7 +228,7 @@ namespace WireMock.RequestBuilders
         /// <inheritdoc cref="IMethodRequestBuilder.UsingVerb"/>
         public IRequestBuilder UsingVerb(params string[] verbs)
         {
-            Check.NotEmpty(verbs, nameof(verbs));
+            Check.NotNullOrEmpty(verbs, nameof(verbs));
 
             _requestMatchers.Add(new RequestMessageMethodMatcher(verbs));
             return this;
@@ -328,7 +328,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithParam(params Func<IDictionary<string, WireMockList<string>>, bool>[] funcs)
         {
-            Check.NotEmpty(funcs, nameof(funcs));
+            Check.NotNullOrEmpty(funcs, nameof(funcs));
 
             _requestMatchers.Add(new RequestMessageParamMatcher(funcs));
             return this;
@@ -363,7 +363,7 @@ namespace WireMock.RequestBuilders
         public IRequestBuilder WithHeader(string name, params IMatcher[] matchers)
         {
             Check.NotNull(name, nameof(name));
-            Check.NotEmpty(matchers, nameof(matchers));
+            Check.NotNullOrEmpty(matchers, nameof(matchers));
 
             _requestMatchers.Add(new RequestMessageHeaderMatcher(name, matchers));
             return this;
@@ -376,7 +376,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithHeader(params Func<IDictionary<string, string[]>, bool>[] funcs)
         {
-            Check.NotEmpty(funcs, nameof(funcs));
+            Check.NotNullOrEmpty(funcs, nameof(funcs));
 
             _requestMatchers.Add(new RequestMessageHeaderMatcher(funcs));
             return this;
@@ -403,7 +403,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithCookie(string name, params IMatcher[] matchers)
         {
-            Check.NotEmpty(matchers, nameof(matchers));
+            Check.NotNullOrEmpty(matchers, nameof(matchers));
 
             _requestMatchers.Add(new RequestMessageCookieMatcher(name, matchers));
             return this;
@@ -416,7 +416,7 @@ namespace WireMock.RequestBuilders
         /// <returns>The <see cref="IRequestBuilder"/>.</returns>
         public IRequestBuilder WithCookie(params Func<IDictionary<string, string>, bool>[] funcs)
         {
-            Check.NotEmpty(funcs, nameof(funcs));
+            Check.NotNullOrEmpty(funcs, nameof(funcs));
 
             _requestMatchers.Add(new RequestMessageCookieMatcher(funcs));
             return this;
diff --git a/src/WireMock.Net/ResponseBuilders/Response.cs b/src/WireMock.Net/ResponseBuilders/Response.cs
index 96ed90ee..920869a9 100644
--- a/src/WireMock.Net/ResponseBuilders/Response.cs
+++ b/src/WireMock.Net/ResponseBuilders/Response.cs
@@ -300,7 +300,7 @@ namespace WireMock.ResponseBuilders
         /// <inheritdoc cref="IProxyResponseBuilder.WithProxy(string, string)"/>
         public IResponseBuilder WithProxy(string proxyUrl, string clientX509Certificate2ThumbprintOrSubjectName = null)
         {
-            Check.NotEmpty(proxyUrl, nameof(proxyUrl));
+            Check.NotNullOrEmpty(proxyUrl, nameof(proxyUrl));
 
             ProxyUrl = proxyUrl;
             ClientX509Certificate2ThumbprintOrSubjectName = clientX509Certificate2ThumbprintOrSubjectName;
diff --git a/src/WireMock.Net/ResponseMessage.cs b/src/WireMock.Net/ResponseMessage.cs
index a6c150e9..cc1f5044 100644
--- a/src/WireMock.Net/ResponseMessage.cs
+++ b/src/WireMock.Net/ResponseMessage.cs
@@ -79,7 +79,7 @@ namespace WireMock
         /// <param name="values">The values.</param>
         public void AddHeader(string name, params string[] values)
         {
-            Check.NotEmpty(values, nameof(values));
+            Check.NotNullOrEmpty(values, nameof(values));
 
             var newHeaderValues = Headers.TryGetValue(name, out WireMockList<string> existingValues)
                 ? values.Union(existingValues).ToArray()
diff --git a/src/WireMock.Net/Server/FluentMockServer.Admin.cs b/src/WireMock.Net/Server/FluentMockServer.Admin.cs
index 46928b6b..8202f58d 100644
--- a/src/WireMock.Net/Server/FluentMockServer.Admin.cs
+++ b/src/WireMock.Net/Server/FluentMockServer.Admin.cs
@@ -146,7 +146,7 @@ namespace WireMock.Server
             {
                 string filenameWithoutExtension = Path.GetFileNameWithoutExtension(args.FullPath);
 
-                if (Guid.TryParse(filenameWithoutExtension, out var guidFromFilename))
+                if (Guid.TryParse(filenameWithoutExtension, out Guid guidFromFilename))
                 {
                     DeleteMapping(guidFromFilename);
                 }
diff --git a/src/WireMock.Net/Server/FluentMockServer.cs b/src/WireMock.Net/Server/FluentMockServer.cs
index 3ab9838c..0ed4e989 100644
--- a/src/WireMock.Net/Server/FluentMockServer.cs
+++ b/src/WireMock.Net/Server/FluentMockServer.cs
@@ -94,7 +94,7 @@ namespace WireMock.Server
         [PublicAPI]
         public static FluentMockServer Start(params string[] urls)
         {
-            Check.NotEmpty(urls, nameof(urls));
+            Check.NotNullOrEmpty(urls, nameof(urls));
 
             return new FluentMockServer(new FluentMockServerSettings
             {
@@ -127,7 +127,7 @@ namespace WireMock.Server
         [PublicAPI]
         public static FluentMockServer StartWithAdminInterface(params string[] urls)
         {
-            Check.NotEmpty(urls, nameof(urls));
+            Check.NotNullOrEmpty(urls, nameof(urls));
 
             return new FluentMockServer(new FluentMockServerSettings
             {
@@ -144,7 +144,7 @@ namespace WireMock.Server
         [PublicAPI]
         public static FluentMockServer StartWithAdminInterfaceAndReadStaticMappings(params string[] urls)
         {
-            Check.NotEmpty(urls, nameof(urls));
+            Check.NotNullOrEmpty(urls, nameof(urls));
 
             return new FluentMockServer(new FluentMockServerSettings
             {
diff --git a/src/WireMock.Net/Validation/Check.cs b/src/WireMock.Net/Validation/Check.cs
index aaf67365..90a298a1 100644
--- a/src/WireMock.Net/Validation/Check.cs
+++ b/src/WireMock.Net/Validation/Check.cs
@@ -23,7 +23,7 @@ namespace WireMock.Validation
 
             if (!condition(value))
             {
-                NotEmpty(parameterName, nameof(parameterName));
+                NotNullOrEmpty(parameterName, nameof(parameterName));
 
                 throw new ArgumentOutOfRangeException(parameterName);
             }
@@ -36,7 +36,7 @@ namespace WireMock.Validation
         {
             if (ReferenceEquals(value, null))
             {
-                NotEmpty(parameterName, nameof(parameterName));
+                NotNullOrEmpty(parameterName, nameof(parameterName));
 
                 throw new ArgumentNullException(parameterName);
             }
@@ -45,15 +45,12 @@ namespace WireMock.Validation
         }
 
         [ContractAnnotation("value:null => halt")]
-        public static T NotNull<T>(
-            [NoEnumeration] T value,
-            [InvokerParameterName] [NotNull] string parameterName,
-            [NotNull] string propertyName)
+        public static T NotNull<T>([NoEnumeration] T value, [InvokerParameterName] [NotNull] string parameterName, [NotNull] string propertyName)
         {
             if (ReferenceEquals(value, null))
             {
-                NotEmpty(parameterName, nameof(parameterName));
-                NotEmpty(propertyName, nameof(propertyName));
+                NotNullOrEmpty(parameterName, nameof(parameterName));
+                NotNullOrEmpty(propertyName, nameof(propertyName));
 
                 throw new ArgumentException(CoreStrings.ArgumentPropertyNull(propertyName, parameterName));
             }
@@ -62,13 +59,13 @@ namespace WireMock.Validation
         }
 
         [ContractAnnotation("value:null => halt")]
-        public static IList<T> NotEmpty<T>(IList<T> value, [InvokerParameterName] [NotNull] string parameterName)
+        public static IList<T> NotNullOrEmpty<T>(IList<T> value, [InvokerParameterName] [NotNull] string parameterName)
         {
             NotNull(value, parameterName);
 
             if (value.Count == 0)
             {
-                NotEmpty(parameterName, nameof(parameterName));
+                NotNullOrEmpty(parameterName, nameof(parameterName));
 
                 throw new ArgumentException(CoreStrings.CollectionArgumentIsEmpty(parameterName));
             }
@@ -77,7 +74,7 @@ namespace WireMock.Validation
         }
 
         [ContractAnnotation("value:null => halt")]
-        public static string NotEmpty(string value, [InvokerParameterName] [NotNull] string parameterName)
+        public static string NotNullOrEmpty(string value, [InvokerParameterName] [NotNull] string parameterName)
         {
             Exception e = null;
             if (ReferenceEquals(value, null))
@@ -91,7 +88,7 @@ namespace WireMock.Validation
 
             if (e != null)
             {
-                NotEmpty(parameterName, nameof(parameterName));
+                NotNullOrEmpty(parameterName, nameof(parameterName));
 
                 throw e;
             }
@@ -104,7 +101,7 @@ namespace WireMock.Validation
             if (!ReferenceEquals(value, null)
                 && (value.Length == 0))
             {
-                NotEmpty(parameterName, nameof(parameterName));
+                NotNullOrEmpty(parameterName, nameof(parameterName));
 
                 throw new ArgumentException(CoreStrings.ArgumentIsEmpty(parameterName));
             }
@@ -119,7 +116,7 @@ namespace WireMock.Validation
 
             if (value.Any(e => e == null))
             {
-                NotEmpty(parameterName, nameof(parameterName));
+                NotNullOrEmpty(parameterName, nameof(parameterName));
 
                 throw new ArgumentException(parameterName);
             }
@@ -131,7 +128,7 @@ namespace WireMock.Validation
         {
             if (!value.GetTypeInfo().IsClass)
             {
-                NotEmpty(parameterName, nameof(parameterName));
+                NotNullOrEmpty(parameterName, nameof(parameterName));
 
                 throw new ArgumentException(CoreStrings.InvalidEntityType(value, parameterName));
             }
diff --git a/src/WireMock.Net/Validation/CoreStrings.cs b/src/WireMock.Net/Validation/CoreStrings.cs
index b6bc3308..dc466b8b 100644
--- a/src/WireMock.Net/Validation/CoreStrings.cs
+++ b/src/WireMock.Net/Validation/CoreStrings.cs
@@ -1,6 +1,4 @@
 using System;
-using System.Globalization;
-using JetBrains.Annotations;
 
 // copied from https://github.com/aspnet/EntityFramework/blob/dev/src/Microsoft.EntityFrameworkCore/Properties/CoreStrings.resx
 namespace WireMock.Validation
@@ -11,33 +9,33 @@ namespace WireMock.Validation
         /// <summary>
         /// The property '{property}' of the argument '{argument}' cannot be null.
         /// </summary>
-        public static string ArgumentPropertyNull([CanBeNull] string property, [CanBeNull] string argument)
+        public static string ArgumentPropertyNull(string property, string argument)
         {
-            return string.Format(CultureInfo.CurrentCulture, $"The property '{property}' of the argument '{argument}' cannot be null.", property, argument);
+            return $"The property '{property}' of the argument '{argument}' cannot be null.";
         }
 
         /// <summary>
         /// The string argument '{argumentName}' cannot be empty.
         /// </summary>
-        public static string ArgumentIsEmpty([CanBeNull] string argumentName)
+        public static string ArgumentIsEmpty(string argumentName)
         {
-            return string.Format(CultureInfo.CurrentCulture, $"The string argument '{argumentName}' cannot be empty.", argumentName);
+            return $"The string argument '{argumentName}' cannot be empty.";
         }
 
         /// <summary>
         /// The entity type '{type}' provided for the argument '{argumentName}' must be a reference type.
         /// </summary>
-        public static string InvalidEntityType([CanBeNull] Type type, [CanBeNull] string argumentName)
+        public static string InvalidEntityType(Type type, string argumentName)
         {
-            return string.Format(CultureInfo.CurrentCulture, $"The entity type '{type}' provided for the argument '{argumentName}' must be a reference type.", type, argumentName);
+            return $"The entity type '{type}' provided for the argument '{argumentName}' must be a reference type.";
         }
 
         /// <summary>
         /// The collection argument '{argumentName}' must contain at least one element.
         /// </summary>
-        public static string CollectionArgumentIsEmpty([CanBeNull] string argumentName)
+        public static string CollectionArgumentIsEmpty(string argumentName)
         {
-            return string.Format(CultureInfo.CurrentCulture, $"The collection argument '{argumentName}' must contain at least one element.", argumentName);
+            return $"The collection argument '{argumentName}' must contain at least one element.";
         }
     }
 }
\ No newline at end of file