diff --git a/src/NLog.MailKit/MailTarget.cs b/src/NLog.MailKit/MailTarget.cs
index 4db2b4f..27659eb 100644
--- a/src/NLog.MailKit/MailTarget.cs
+++ b/src/NLog.MailKit/MailTarget.cs
@@ -253,6 +253,8 @@ protected override void Write(AsyncLogEventInfo logEvent)
             Write((IList<AsyncLogEventInfo>)new[] { logEvent });
         }
 
+#if !NETSTANDARD2_0
+
         /// <summary>
         /// NOTE! Will soon be marked obsolete. Instead override Write(IList{AsyncLogEventInfo} logEvents)
         /// 
@@ -266,6 +268,8 @@ protected override void Write(AsyncLogEventInfo[] logEvents)
             Write((IList<AsyncLogEventInfo>)logEvents);
         }
 
+#endif
+
         /// <summary>
         /// Renders an array logging events.
         /// </summary>
diff --git a/src/NLog.MailKit/NLog.MailKit.csproj b/src/NLog.MailKit/NLog.MailKit.csproj
index 2815b6c..2f87757 100644
--- a/src/NLog.MailKit/NLog.MailKit.csproj
+++ b/src/NLog.MailKit/NLog.MailKit.csproj
@@ -1,21 +1,20 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>netstandard1.4</TargetFramework>
-    <Version>1.1.1</Version>
+    <TargetFrameworks>netstandard1.4;net40;netstandard2.0</TargetFrameworks>
+    <Version>2.0</Version>
     <Authors>Julian Verdurmen</Authors>
     <Company>NLog</Company>
-    <Description>
-      NLog Mail Target for .NET Core, using MailKit.
+    <Description>NLog Mail Target for .NET Core, using MailKit.
       
-      As System.Net.Mail isn't ported to .NET Core (yet), the original Mail Target of NLog isn't working when using .NET Core. 
+As System.Net.Mail isn't ported to .NET Core (yet), the original Mail Target of NLog isn't working when using .NET Core. 
       
-      This package add the mail target to NLog and has the same options as the original Mail Target. 
+This package add the mail target to NLog and has the same options as the original Mail Target. 
       
-      Compared to the original MailTarget, the following options aren't implemented:
+Compared to the original MailTarget, the following options aren't implemented:
 
-      - PickupDirectory
-      - NTLM auth
-    </Description>
+ - PickupDirectory
+ - NTLM auth
+</Description>
     <PackageProjectUrl>https://github.com/NLog/NLog.MailKit</PackageProjectUrl>
     <PackageLicenseUrl>https://raw.githubusercontent.com/NLog/NLog.MailKit/master/LICENSE</PackageLicenseUrl>
     <PackageIconUrl>http://nlog-project.org/N.png</PackageIconUrl>
@@ -26,21 +25,33 @@
     <AssemblyOriginatorKeyFile>NLog.snk</AssemblyOriginatorKeyFile>
     <DelaySign>False</DelaySign>
     <PackageReleaseNotes>
-      1.1.1: Updated dependencies
-      1.1.0: Added SkipCertificateValidation option
-    </PackageReleaseNotes>
-    <AssemblyVersion>1.0.0.0</AssemblyVersion>
+2.0: .NET 4+ and .NET standard 2 support. 
+      
+Small breaking change, SmtpAuthenticationMode has been moved to this dll.
+      
+1.1.1: Updated dependencies
+1.1.0: Added SkipCertificateValidation option
+</PackageReleaseNotes>
+    <AssemblyVersion>2.0.0.0</AssemblyVersion>
     <!--AssemblyVersion: keep 1.0.0.0-->
-    <FileVersion>0.1.0.0</FileVersion>
+    <FileVersion>2.0.0.0</FileVersion>
     <!-- FileVersion = AssemblyFileVersionAttribute, patched by AppVeyor -->
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
-    <DocumentationFile>bin\Release\netstandard1.3\NLog.MailKit.xml</DocumentationFile>
+    <DocumentationFile>bin\Release\$(TargetFramework)\NLog.MailKit.xml</DocumentationFile>
     <OutputPath>bin\Release\</OutputPath>
-    <DefineConstants>TRACE;RELEASE</DefineConstants>
+    <DefineConstants>RELEASE</DefineConstants>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="MailKit" Version="1.16.2" />
-    <PackageReference Include="NLog" Version="5.0.0-beta09" />
+    <PackageReference Include="MailKit" Version="1.18.1.1" />
+  </ItemGroup>
+  <ItemGroup Condition=" '$(TargetFramework)' == 'net40' ">
+    <PackageReference Include="NLog" Version="4.4.12" />
+  </ItemGroup>
+  <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard1.4' ">
+    <PackageReference Include="NLog" Version="5.0.0-beta11" />
+  </ItemGroup>
+  <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.0' ">
+    <PackageReference Include="NLog" Version="4.5.0-beta03" />
   </ItemGroup>
 </Project>
diff --git a/src/NLog.MailKit/SmtpAuthenticationMode.cs b/src/NLog.MailKit/SmtpAuthenticationMode.cs
new file mode 100644
index 0000000..c2e6a36
--- /dev/null
+++ b/src/NLog.MailKit/SmtpAuthenticationMode.cs
@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace NLog.MailKit
+{
+    /// <summary>
+    /// SMTP authentication modes.
+    /// </summary>
+    public enum SmtpAuthenticationMode
+    {
+        /// <summary>
+        /// No authentication.
+        /// </summary>
+        None,
+
+        /// <summary>
+        /// Basic - username and password.
+        /// </summary>
+        Basic,
+
+        /// <summary>
+        /// NTLM Authentication.
+        /// </summary>
+        Ntlm,
+    }
+}
diff --git a/test/NLog.MailKit.Tests/NLog.MailKit.Tests.csproj b/test/NLog.MailKit.Tests/NLog.MailKit.Tests.csproj
index 386e412..12ff5f2 100644
--- a/test/NLog.MailKit.Tests/NLog.MailKit.Tests.csproj
+++ b/test/NLog.MailKit.Tests/NLog.MailKit.Tests.csproj
@@ -1,14 +1,14 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>    
-    <TargetFramework>netcoreapp1.1</TargetFramework>
+    <TargetFrameworks>netcoreapp1.1;net461;netcoreapp2.0</TargetFrameworks>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.0.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.5.0-preview-20171009-10" />
     <PackageReference Include="SmtpServer" Version="2.2.0" />
-    <PackageReference Include="xunit" Version="2.2.0" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="2.2.0" />
+    <PackageReference Include="xunit" Version="2.3.0" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.3.0" />
   </ItemGroup>
 
   <ItemGroup>