diff --git a/System.Device.Spi/System.Device.Spi.nfproj b/System.Device.Spi/System.Device.Spi.nfproj
index 6a55ed85b..553b6baf8 100644
--- a/System.Device.Spi/System.Device.Spi.nfproj
+++ b/System.Device.Spi/System.Device.Spi.nfproj
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="Current" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup Label="Globals">
     <NanoFrameworkProjectSystemPath>$(MSBuildToolsPath)..\..\..\nanoFramework\v1.0\</NanoFrameworkProjectSystemPath>
@@ -41,7 +41,7 @@
     </NFMDP_PE_ExcludeClassByName>
   </ItemGroup>
   <ItemGroup>
-    <NFMDP_PE_LoadHints Include="..\packages\nanoFramework.CoreLibrary.1.10.4-preview.4\lib\mscorlib.dll">
+    <NFMDP_PE_LoadHints Include="..\packages\nanoFramework.CoreLibrary.1.10.4-preview.6\lib\mscorlib.dll">
       <InProject>false</InProject>
     </NFMDP_PE_LoadHints>
   </ItemGroup>
@@ -61,7 +61,7 @@
   </ItemGroup>
   <ItemGroup>
     <Reference Include="mscorlib, Version=1.10.4.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\packages\nanoFramework.CoreLibrary.1.10.4-preview.4\lib\mscorlib.dll</HintPath>
+      <HintPath>..\packages\nanoFramework.CoreLibrary.1.10.4-preview.6\lib\mscorlib.dll</HintPath>
       <Private>True</Private>
     </Reference>
     <Reference Include="nanoFramework.Runtime.Events, Version=1.9.0.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
diff --git a/System.Device.Spi/packages.config b/System.Device.Spi/packages.config
index f478c8239..0530f381d 100644
--- a/System.Device.Spi/packages.config
+++ b/System.Device.Spi/packages.config
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="nanoFramework.CoreLibrary" version="1.10.4-preview.4" targetFramework="netnanoframework10" />
+  <package id="nanoFramework.CoreLibrary" version="1.10.4-preview.6" targetFramework="netnanoframework10" />
   <package id="nanoFramework.Runtime.Events" version="1.9.0-preview.24" targetFramework="netnanoframework10" />
   <package id="nanoFramework.System.Device.Gpio" version="1.0.0-preview.38" targetFramework="netnanoframework10" />
   <package id="Nerdbank.GitVersioning" version="3.4.194" developmentDependency="true" targetFramework="netnanoframework10" />
diff --git a/Test/SpiHardwareUnitTests/SpiHardwareUnitTests.nfproj b/Test/SpiHardwareUnitTests/SpiHardwareUnitTests.nfproj
index 233bc8e29..452518b2f 100644
--- a/Test/SpiHardwareUnitTests/SpiHardwareUnitTests.nfproj
+++ b/Test/SpiHardwareUnitTests/SpiHardwareUnitTests.nfproj
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="Current" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup Label="Globals">
     <NanoFrameworkProjectSystemPath>$(MSBuildToolsPath)..\..\..\nanoFramework\v1.0\</NanoFrameworkProjectSystemPath>
@@ -32,7 +32,7 @@
   </ItemGroup>
   <ItemGroup>
     <Reference Include="mscorlib, Version=1.10.4.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\..\packages\nanoFramework.CoreLibrary.1.10.4-preview.4\lib\mscorlib.dll</HintPath>
+      <HintPath>..\..\packages\nanoFramework.CoreLibrary.1.10.4-preview.6\lib\mscorlib.dll</HintPath>
       <Private>True</Private>
     </Reference>
     <Reference Include="nanoFramework.Runtime.Events, Version=1.9.0.0, Culture=neutral, PublicKeyToken=c07d481e9758c731">
diff --git a/Test/SpiHardwareUnitTests/packages.config b/Test/SpiHardwareUnitTests/packages.config
index 265dc4c68..dcdacc7ff 100644
--- a/Test/SpiHardwareUnitTests/packages.config
+++ b/Test/SpiHardwareUnitTests/packages.config
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="nanoFramework.CoreLibrary" version="1.10.4-preview.4" targetFramework="netnanoframework10" />
+  <package id="nanoFramework.CoreLibrary" version="1.10.4-preview.6" targetFramework="netnanoframework10" />
   <package id="nanoFramework.Runtime.Events" version="1.9.0-preview.24" targetFramework="netnanoframework10" />
   <package id="nanoFramework.System.Device.Gpio" version="1.0.0-preview.38" targetFramework="netnanoframework10" />
   <package id="nanoFramework.TestFramework" version="1.0.114" targetFramework="netnanoframework10" developmentDependency="true" />
diff --git a/nanoFramework.System.Device.Spi.nuspec b/nanoFramework.System.Device.Spi.nuspec
index 00894ccff..f24b44c6d 100644
--- a/nanoFramework.System.Device.Spi.nuspec
+++ b/nanoFramework.System.Device.Spi.nuspec
@@ -21,7 +21,7 @@ This package requires a target with System.Device.Spi v$nativeVersion$ (checksum
     <summary>System.Device.Spi assembly for .NET nanoFramework C# projects</summary>
     <tags>nanoFramework C# csharp netmf netnf System.Device.Spi</tags>
     <dependencies>
-      <dependency id="nanoFramework.CoreLibrary" version="1.10.4-preview.4" />
+      <dependency id="nanoFramework.CoreLibrary" version="1.10.4-preview.6" />
     </dependencies>
   </metadata>
   <files>