diff --git a/PrepareEnv/Examples/Zetbox.Cli.exe.config b/PrepareEnv/Examples/Zetbox.Cli.exe.config
index 9bf2dd83bb..3d8c738dd8 100644
--- a/PrepareEnv/Examples/Zetbox.Cli.exe.config
+++ b/PrepareEnv/Examples/Zetbox.Cli.exe.config
@@ -162,7 +162,7 @@
   <system.data>
     <DbProviderFactories>
       <remove invariant="Npgsql" />
-      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.2, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
+      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.6, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
     </DbProviderFactories>
   </system.data>
   <startup>
diff --git a/PrepareEnv/PrepareEnv.csproj b/PrepareEnv/PrepareEnv.csproj
index c0b8f3bea3..c9c9ad129c 100644
--- a/PrepareEnv/PrepareEnv.csproj
+++ b/PrepareEnv/PrepareEnv.csproj
@@ -57,12 +57,10 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="Mono.Security, Version=4.0.0.0, Culture=neutral, PublicKeyToken=0738eb9f132ed756, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\packages\Npgsql.2.2.2\lib\net40\Mono.Security.dll</HintPath>
+      <HintPath>..\packages\Npgsql.2.2.6\lib\net45\Mono.Security.dll</HintPath>
     </Reference>
-    <Reference Include="Npgsql, Version=2.2.2.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\packages\Npgsql.2.2.2\lib\net40\Npgsql.dll</HintPath>
+    <Reference Include="Npgsql, Version=2.2.6.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7, processorArchitecture=MSIL">
+      <HintPath>..\packages\Npgsql.2.2.6\lib\net45\Npgsql.dll</HintPath>
     </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core" />
diff --git a/PrepareEnv/packages.config b/PrepareEnv/packages.config
index c90a3f3377..5238b32745 100644
--- a/PrepareEnv/packages.config
+++ b/PrepareEnv/packages.config
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
   <package id="GitVersionTask" version="5.3.7" targetFramework="net462" developmentDependency="true" />
-  <package id="Npgsql" version="2.2.2" targetFramework="net40" requireReinstallation="true" />
+  <package id="Npgsql" version="2.2.6" targetFramework="net462" />
   <package id="UtilPack.NuGet.MSBuild" version="2.9.1" targetFramework="net462" developmentDependency="true" />
 </packages>
\ No newline at end of file
diff --git a/Tests/CompleteTests/App.config b/Tests/CompleteTests/App.config
index 4f4d95a730..5be20a8bfa 100644
--- a/Tests/CompleteTests/App.config
+++ b/Tests/CompleteTests/App.config
@@ -115,13 +115,17 @@
         <assemblyIdentity name="System.Runtime.CompilerServices.Unsafe" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
         <bindingRedirect oldVersion="0.0.0.0-4.0.4.1" newVersion="4.0.4.1" />
       </dependentAssembly>
+      <dependentAssembly>
+        <assemblyIdentity name="Npgsql" publicKeyToken="5d8b90d52f46fda7" culture="neutral" />
+        <bindingRedirect oldVersion="0.0.0.0-2.2.6.0" newVersion="2.2.6.0" />
+      </dependentAssembly>
     </assemblyBinding>
   </runtime>
   <!-- See http://npgsql.projects.postgresql.org/docs/manual/UserManual.html "Using Npgsql with ProviderFactory" -->
   <system.data>
     <DbProviderFactories>
       <remove invariant="Npgsql" />
-      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.2, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
+      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.6, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
     </DbProviderFactories>
   </system.data>
   <!--
diff --git a/Tests/Zetbox.DalProvider.EF.Tests/App.config b/Tests/Zetbox.DalProvider.EF.Tests/App.config
index 011f872ea4..d4c7c57192 100644
--- a/Tests/Zetbox.DalProvider.EF.Tests/App.config
+++ b/Tests/Zetbox.DalProvider.EF.Tests/App.config
@@ -40,7 +40,7 @@
   <system.data>
     <DbProviderFactories>
       <remove invariant="Npgsql" />
-      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.2, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
+      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.6, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
     </DbProviderFactories>
   </system.data>
 <startup><supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.2" /></startup>
@@ -58,6 +58,10 @@
         <assemblyIdentity name="System.Runtime.Extensions" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
         <bindingRedirect oldVersion="0.0.0.0-4.1.1.0" newVersion="4.1.1.0" />
       </dependentAssembly>
+      <dependentAssembly>
+        <assemblyIdentity name="Npgsql" publicKeyToken="5d8b90d52f46fda7" culture="neutral" />
+        <bindingRedirect oldVersion="0.0.0.0-2.2.6.0" newVersion="2.2.6.0" />
+      </dependentAssembly>
     </assemblyBinding>
   </runtime>
 </configuration>
diff --git a/Tests/Zetbox.IntegrationTests/App.config b/Tests/Zetbox.IntegrationTests/App.config
index 6a766e4701..64010fb99e 100644
--- a/Tests/Zetbox.IntegrationTests/App.config
+++ b/Tests/Zetbox.IntegrationTests/App.config
@@ -78,7 +78,7 @@
   <system.data>
     <DbProviderFactories>
       <remove invariant="Npgsql" />
-      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.2, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
+      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.6, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
     </DbProviderFactories>
   </system.data>
   <!--
diff --git a/Tests/Zetbox.Server.Tests/App.config b/Tests/Zetbox.Server.Tests/App.config
index f01bb26801..05cb60c37a 100644
--- a/Tests/Zetbox.Server.Tests/App.config
+++ b/Tests/Zetbox.Server.Tests/App.config
@@ -119,7 +119,7 @@
   <system.data>
     <DbProviderFactories>
       <remove invariant="Npgsql" />
-      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.2, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
+      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.6, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
     </DbProviderFactories>
   </system.data>
   <startup>
diff --git a/Zetbox.Cli/app.config b/Zetbox.Cli/app.config
index a7a9d6249a..6264468d00 100644
--- a/Zetbox.Cli/app.config
+++ b/Zetbox.Cli/app.config
@@ -166,7 +166,7 @@
   <system.data>
     <DbProviderFactories>
       <remove invariant="Npgsql" />
-      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.2, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
+      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.6, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
     </DbProviderFactories>
   </system.data>
   <startup>
diff --git a/Zetbox.DalProvider.Ef/Zetbox.DalProvider.Ef.csproj b/Zetbox.DalProvider.Ef/Zetbox.DalProvider.Ef.csproj
index 9c95300351..0045ae0edc 100644
--- a/Zetbox.DalProvider.Ef/Zetbox.DalProvider.Ef.csproj
+++ b/Zetbox.DalProvider.Ef/Zetbox.DalProvider.Ef.csproj
@@ -72,15 +72,13 @@
     </Reference>
     <Reference Include="Microsoft.CSharp" />
     <Reference Include="Mono.Security, Version=4.0.0.0, Culture=neutral, PublicKeyToken=0738eb9f132ed756, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\packages\Npgsql.2.2.2\lib\net40\Mono.Security.dll</HintPath>
+      <HintPath>..\packages\Npgsql.2.2.6\lib\net45\Mono.Security.dll</HintPath>
     </Reference>
-    <Reference Include="Npgsql, Version=2.2.2.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\packages\Npgsql.2.2.2\lib\net40\Npgsql.dll</HintPath>
+    <Reference Include="Npgsql, Version=2.2.6.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7, processorArchitecture=MSIL">
+      <HintPath>..\packages\Npgsql.2.2.6\lib\net45\Npgsql.dll</HintPath>
     </Reference>
-    <Reference Include="Npgsql.EntityFrameworkLegacy">
-      <HintPath>..\packages\Npgsql.EntityFrameworkLegacy.2.2.2\lib\net40\Npgsql.EntityFrameworkLegacy.dll</HintPath>
+    <Reference Include="Npgsql.EntityFrameworkLegacy, Version=2.2.6.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7, processorArchitecture=MSIL">
+      <HintPath>..\packages\Npgsql.EntityFrameworkLegacy.2.2.6\lib\net45\Npgsql.EntityFrameworkLegacy.dll</HintPath>
     </Reference>
     <Reference Include="System" />
     <Reference Include="System.ComponentModel.DataAnnotations" />
diff --git a/Zetbox.DalProvider.Ef/packages.config b/Zetbox.DalProvider.Ef/packages.config
index eb0833cb08..d008fa2f44 100644
--- a/Zetbox.DalProvider.Ef/packages.config
+++ b/Zetbox.DalProvider.Ef/packages.config
@@ -4,7 +4,7 @@
   <package id="EntityFramework" version="4.1.10311.0" targetFramework="net40" />
   <package id="GitVersionTask" version="5.3.7" targetFramework="net462" developmentDependency="true" />
   <package id="log4net" version="2.0.12" targetFramework="net462" />
-  <package id="Npgsql" version="2.2.2" targetFramework="net40" requireReinstallation="true" />
-  <package id="Npgsql.EntityFrameworkLegacy" version="2.2.2" targetFramework="net40" requireReinstallation="true" />
+  <package id="Npgsql" version="2.2.6" targetFramework="net462" />
+  <package id="Npgsql.EntityFrameworkLegacy" version="2.2.6" targetFramework="net462" />
   <package id="UtilPack.NuGet.MSBuild" version="2.9.1" targetFramework="net462" developmentDependency="true" />
 </packages>
\ No newline at end of file
diff --git a/Zetbox.Server.HttpService/Web.config b/Zetbox.Server.HttpService/Web.config
index 0cb0ca7e72..7144542e10 100644
--- a/Zetbox.Server.HttpService/Web.config
+++ b/Zetbox.Server.HttpService/Web.config
@@ -227,7 +227,7 @@
   <system.data>
     <DbProviderFactories>
       <remove invariant="Npgsql" />
-      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.2, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
+      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.6, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
     </DbProviderFactories>
   </system.data>
 </configuration>
\ No newline at end of file
diff --git a/Zetbox.Server.Service/app.config b/Zetbox.Server.Service/app.config
index 525d79f92d..efa7f2907e 100644
--- a/Zetbox.Server.Service/app.config
+++ b/Zetbox.Server.Service/app.config
@@ -179,7 +179,7 @@
       <connectionString value="data source=localhost\sqlexpress;initial catalog=zetbox;integrated security=true" />      
       <commandText value="INSERT INTO base.[ExceptionLog] ([Date],[Thread],[Level],[Logger],[Message], [Exception]) VALUES (@log_date, @thread, @log_level, @logger, @message, @exception)" />
       -->
-      <connectionType value="Npgsql.NpgsqlConnection, Npgsql, Version=2.2.2, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
+      <connectionType value="Npgsql.NpgsqlConnection, Npgsql, Version=2.2.6, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
       <connectionString value="Server=localhost;Port=5432;Database=zetbox;User Id=zetbox;Password=b-cXqMyXEYea2kkjUhkS" />
       <commandText value="INSERT INTO &quot;base&quot;.&quot;ExceptionLog&quot; (&quot;Date&quot;,&quot;Thread&quot;,&quot;Level&quot;,&quot;Logger&quot;,&quot;Message&quot;, &quot;Exception&quot;) VALUES (:log_date, :thread, :log_level, :logger, :message, :exception)" />
       <parameter>
@@ -374,7 +374,7 @@
   <system.data>
     <DbProviderFactories>
       <remove invariant="Npgsql" />
-      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.2, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
+      <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.6, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" />
     </DbProviderFactories>
   </system.data>
   <startup>
diff --git a/Zetbox.Server/Zetbox.Server.csproj b/Zetbox.Server/Zetbox.Server.csproj
index a241360023..d7ee66758d 100644
--- a/Zetbox.Server/Zetbox.Server.csproj
+++ b/Zetbox.Server/Zetbox.Server.csproj
@@ -71,12 +71,10 @@
     <Reference Include="Microsoft.Build.Framework" />
     <Reference Include="Microsoft.CSharp" />
     <Reference Include="Mono.Security, Version=4.0.0.0, Culture=neutral, PublicKeyToken=0738eb9f132ed756, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\packages\Npgsql.2.2.2\lib\net40\Mono.Security.dll</HintPath>
+      <HintPath>..\packages\Npgsql.2.2.6\lib\net45\Mono.Security.dll</HintPath>
     </Reference>
-    <Reference Include="Npgsql, Version=2.2.2.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\packages\Npgsql.2.2.2\lib\net40\Npgsql.dll</HintPath>
+    <Reference Include="Npgsql, Version=2.2.6.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7, processorArchitecture=MSIL">
+      <HintPath>..\packages\Npgsql.2.2.6\lib\net45\Npgsql.dll</HintPath>
     </Reference>
     <Reference Include="System" />
     <Reference Include="System.configuration" />
diff --git a/Zetbox.Server/packages.config b/Zetbox.Server/packages.config
index 2d4b97d1d3..e3649cb3b8 100644
--- a/Zetbox.Server/packages.config
+++ b/Zetbox.Server/packages.config
@@ -3,6 +3,6 @@
   <package id="Autofac" version="3.5.2" targetFramework="net462" />
   <package id="GitVersionTask" version="5.3.7" targetFramework="net462" developmentDependency="true" />
   <package id="log4net" version="2.0.12" targetFramework="net462" />
-  <package id="Npgsql" version="2.2.2" targetFramework="net40" requireReinstallation="true" />
+  <package id="Npgsql" version="2.2.6" targetFramework="net462" />
   <package id="UtilPack.NuGet.MSBuild" version="2.9.1" targetFramework="net462" developmentDependency="true" />
 </packages>
\ No newline at end of file
diff --git a/publish/zetboxBasic-Server.nuspec.template b/publish/zetboxBasic-Server.nuspec.template
index 8fdb725eab..7042912214 100644
--- a/publish/zetboxBasic-Server.nuspec.template
+++ b/publish/zetboxBasic-Server.nuspec.template
@@ -16,7 +16,7 @@
     <dependencies>
       <dependency id="zetboxBasic" version="[##version##]" />
       <dependency id="zetboxBasic-Common" version="[##version##]" />
-      <dependency id="Npgsql" version="[2.2.2,3)" />
+      <dependency id="Npgsql" version="[2.2.6,3)" />
     </dependencies>
   </metadata>
   <files>