diff --git a/Directory.Build.props b/Directory.Build.props
index 96dfe335c..3c8502449 100644
--- a/Directory.Build.props
+++ b/Directory.Build.props
@@ -103,7 +103,7 @@
     <BaseOutputPath>$(RootDir)bin\$(Configuration)</BaseOutputPath>
     <OutputPath>$(BaseOutputPath)</OutputPath>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
-    <WarningsNotAsErrors>618;429;219;1717;162;414</WarningsNotAsErrors>
+    <WarningsNotAsErrors>618;429;219;1717;162;414;NU1900;CA1859;CA1861</WarningsNotAsErrors>
     <NoWarn>1591;1584;1574;1685;1573</NoWarn>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
diff --git a/Src/IronPython/IronPython.csproj b/Src/IronPython/IronPython.csproj
index f9749b961..8ed0a8e56 100644
--- a/Src/IronPython/IronPython.csproj
+++ b/Src/IronPython/IronPython.csproj
@@ -61,7 +61,7 @@
     </PackageReference>
   </ItemGroup>
 
-  <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.0' ">
+  <ItemGroup Condition=" '$(TargetFramework)' != 'net45' ">
     <PackageReference Include="System.Text.Encoding.CodePages" Version="4.6.0" />
   </ItemGroup>
 
diff --git a/Src/IronPython/Runtime/PythonContext.cs b/Src/IronPython/Runtime/PythonContext.cs
index b604236ed..25a496c7e 100644
--- a/Src/IronPython/Runtime/PythonContext.cs
+++ b/Src/IronPython/Runtime/PythonContext.cs
@@ -44,6 +44,15 @@ namespace IronPython.Runtime
     public delegate int HashDelegate(object o, ref HashDelegate dlg);
 
     public sealed partial class PythonContext : LanguageContext {
+        static PythonContext() {
+            try {
+#if NETCOREAPP || NETSTANDARD
+                Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
+#endif
+            } catch {
+            }
+        }
+
         internal static readonly string/*!*/ IronPythonDisplayName = CurrentVersion.DisplayName;
         internal const string/*!*/ IronPythonNames = "IronPython;Python;py";
         internal const string/*!*/ IronPythonFileExtensions = ".py";