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       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PrecompiledHeaderFile>pch.h</PrecompiledHeaderFile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <EnableParallelCodeGeneration>true</EnableParallelCodeGeneration>
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <ControlFlowGuard>false</ControlFlowGuard>
diff --git a/Ricoh2A03/src/Ricoh2A03.vcxproj b/Ricoh2A03/src/Ricoh2A03.vcxproj
index 51595d9..d05076e 100644
--- a/Ricoh2A03/src/Ricoh2A03.vcxproj
+++ b/Ricoh2A03/src/Ricoh2A03.vcxproj
@@ -22,6 +22,7 @@
     <VCProjectVersion>15.0</VCProjectVersion>
     <ProjectGuid>{CCF67510-C3BD-40FD-BF13-9FA9B9BCFE43}</ProjectGuid>
     <RootNamespace>Ricoh2A03</RootNamespace>
+    <WindowsTargetPlatformVersion>10.0</WindowsTargetPlatformVersion>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
@@ -85,7 +86,7 @@
       <WarningLevel>Level3</WarningLevel>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <PrecompiledHeader>Use</PrecompiledHeader>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <EnableParallelCodeGeneration>true</EnableParallelCodeGeneration>
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <ControlFlowGuard>false</ControlFlowGuard>
@@ -102,7 +103,7 @@
       <Optimization>Disabled</Optimization>
       <SDLCheck>true</SDLCheck>
       <PrecompiledHeader>Use</PrecompiledHeader>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
     </ClCompile>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
@@ -111,7 +112,7 @@
       <Optimization>Disabled</Optimization>
       <SDLCheck>true</SDLCheck>
       <PrecompiledHeader>Use</PrecompiledHeader>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
     </ClCompile>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
@@ -119,7 +120,7 @@
       <WarningLevel>Level3</WarningLevel>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <PrecompiledHeader>Use</PrecompiledHeader>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <EnableParallelCodeGeneration>true</EnableParallelCodeGeneration>
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <ControlFlowGuard>false</ControlFlowGuard>
diff --git a/Z80/fusetest_Z80/fusetest_Z80.vcxproj b/Z80/fusetest_Z80/fusetest_Z80.vcxproj
index b0e9db3..6e0d7a2 100644
--- a/Z80/fusetest_Z80/fusetest_Z80.vcxproj
+++ b/Z80/fusetest_Z80/fusetest_Z80.vcxproj
@@ -24,6 +24,7 @@
     <Keyword>Win32Proj</Keyword>
     <RootNamespace>fuse_test_Z80</RootNamespace>
     <ProjectName>fusetest_Z80</ProjectName>
+    <WindowsTargetPlatformVersion>10.0</WindowsTargetPlatformVersion>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
@@ -94,7 +95,7 @@
       <PreprocessorDefinitions>NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <EnableParallelCodeGeneration>true</EnableParallelCodeGeneration>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <ControlFlowGuard>false</ControlFlowGuard>
       <InlineFunctionExpansion>AnySuitable</InlineFunctionExpansion>
     </ClCompile>
@@ -110,7 +111,7 @@
       <WarningLevel>Level3</WarningLevel>
       <Optimization>Disabled</Optimization>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <SDLCheck>true</SDLCheck>
     </ClCompile>
     <Link>
@@ -123,7 +124,7 @@
       <WarningLevel>Level3</WarningLevel>
       <Optimization>Disabled</Optimization>
       <PreprocessorDefinitions>_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <SDLCheck>true</SDLCheck>
     </ClCompile>
     <Link>
@@ -138,7 +139,7 @@
       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <EnableParallelCodeGeneration>true</EnableParallelCodeGeneration>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <ControlFlowGuard>false</ControlFlowGuard>
       <InlineFunctionExpansion>AnySuitable</InlineFunctionExpansion>
     </ClCompile>
diff --git a/Z80/test/test_Z80.vcxproj b/Z80/test/test_Z80.vcxproj
index bbab548..43c2f50 100644
--- a/Z80/test/test_Z80.vcxproj
+++ b/Z80/test/test_Z80.vcxproj
@@ -23,6 +23,7 @@
     <ProjectGuid>{F8EE7116-0D75-4C82-BA9E-409F69F5D47C}</ProjectGuid>
     <Keyword>Win32Proj</Keyword>
     <RootNamespace>test_Z80</RootNamespace>
+    <WindowsTargetPlatformVersion>10.0</WindowsTargetPlatformVersion>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
@@ -86,7 +87,7 @@
       <PreprocessorDefinitions>NDEBUG;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <EnableParallelCodeGeneration>true</EnableParallelCodeGeneration>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <ControlFlowGuard>false</ControlFlowGuard>
       <InlineFunctionExpansion>AnySuitable</InlineFunctionExpansion>
     </ClCompile>
@@ -103,7 +104,7 @@
       <WarningLevel>Level3</WarningLevel>
       <Optimization>Disabled</Optimization>
       <PreprocessorDefinitions>WIN32;_DEBUG;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <SDLCheck>true</SDLCheck>
     </ClCompile>
     <Link />
@@ -117,7 +118,7 @@
       <WarningLevel>Level3</WarningLevel>
       <Optimization>Disabled</Optimization>
       <PreprocessorDefinitions>_DEBUG;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <SDLCheck>true</SDLCheck>
     </ClCompile>
     <Link />
@@ -133,7 +134,7 @@
       <PreprocessorDefinitions>WIN32;NDEBUG;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <EnableParallelCodeGeneration>true</EnableParallelCodeGeneration>
-      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard>stdcpp20</LanguageStandard>
       <ControlFlowGuard>false</ControlFlowGuard>
       <InlineFunctionExpansion>AnySuitable</InlineFunctionExpansion>
     </ClCompile>