diff --git a/icu4c/source/allinone/Build.Windows.ProjectConfiguration.props b/icu4c/source/allinone/Build.Windows.ProjectConfiguration.props
index 5d7e3344889..222c0aa0b80 100644
--- a/icu4c/source/allinone/Build.Windows.ProjectConfiguration.props
+++ b/icu4c/source/allinone/Build.Windows.ProjectConfiguration.props
@@ -96,6 +96,9 @@
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
       <!-- Enable parallel compilation for faster builds. -->
       <MultiProcessorCompilation>true</MultiProcessorCompilation>
+      <!-- Set the C/C++ versions supported. -->
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
     </ClCompile>
     <ResourceCompile>
       <Culture>0x0409</Culture>
diff --git a/icu4c/source/allinone/Build.Windows.UWP.ProjectConfiguration.props b/icu4c/source/allinone/Build.Windows.UWP.ProjectConfiguration.props
index 948b7c4f98b..12c29b3291b 100644
--- a/icu4c/source/allinone/Build.Windows.UWP.ProjectConfiguration.props
+++ b/icu4c/source/allinone/Build.Windows.UWP.ProjectConfiguration.props
@@ -45,6 +45,9 @@
         %(PreprocessorDefinitions);
         U_PLATFORM_HAS_WINUWP_API=1;
       </PreprocessorDefinitions>
+      <!-- Set the C/C++ versions supported. -->
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
     </ClCompile>
     <ResourceCompile>
       <PreprocessorDefinitions>
diff --git a/icu4c/source/common/common.vcxproj b/icu4c/source/common/common.vcxproj
index 56fe146ed7a..1fdf3bda895 100644
--- a/icu4c/source/common/common.vcxproj
+++ b/icu4c/source/common/common.vcxproj
@@ -34,10 +34,7 @@
       <TypeLibraryName>$(OutDir)\icuuc.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <PreprocessorDefinitions>U_ATTRIBUTE_DEPRECATED=;U_COMMON_IMPLEMENTATION;U_PLATFORM_USES_ONLY_WIN32_API=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <WarningLevel>Level3</WarningLevel>
       <CompileAs>Default</CompileAs>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
diff --git a/icu4c/source/common/common_uwp.vcxproj b/icu4c/source/common/common_uwp.vcxproj
index 7379eade57f..177455dc57b 100644
--- a/icu4c/source/common/common_uwp.vcxproj
+++ b/icu4c/source/common/common_uwp.vcxproj
@@ -72,8 +72,6 @@
       <TypeLibraryName>$(OutDir)\icuuc.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <!-- U_DISABLE_RENAMING -->
       <!-- U_HIDE_DRAFT_API & U_HIDE_DEPRECATED_API -->
@@ -82,7 +80,6 @@
       <ExceptionHandling>
       </ExceptionHandling>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <TreatWChar_tAsBuiltInType>true</TreatWChar_tAsBuiltInType>
       <WarningLevel>Level3</WarningLevel>
       <SuppressStartupBanner>true</SuppressStartupBanner>
diff --git a/icu4c/source/extra/uconv/uconv.vcxproj b/icu4c/source/extra/uconv/uconv.vcxproj
index adfe06c87d3..a0cc5adf092 100644
--- a/icu4c/source/extra/uconv/uconv.vcxproj
+++ b/icu4c/source/extra/uconv/uconv.vcxproj
@@ -34,11 +34,8 @@
       <TypeLibraryName>$(OutDir)\uconv.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <WarningLevel>Level3</WarningLevel>
       <CompileAs>Default</CompileAs>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <AdditionalIncludeDirectories>..\..\..\include;..\..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>UCONVMSG_LINK;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PrecompiledHeaderOutputFile>$(OutDir)\uconv.pch</PrecompiledHeaderOutputFile>
diff --git a/icu4c/source/i18n/calendar.cpp b/icu4c/source/i18n/calendar.cpp
index 2bd2cc9aa9d..33050553488 100644
--- a/icu4c/source/i18n/calendar.cpp
+++ b/icu4c/source/i18n/calendar.cpp
@@ -3695,13 +3695,15 @@ int32_t Calendar::handleGetExtendedYearFromWeekFields(int32_t yearWoy, int32_t w
 
 int32_t Calendar::handleGetMonthLength(int32_t extendedYear, int32_t month) const
 {
-    return handleComputeMonthStart(extendedYear, month+1, true) -
-        handleComputeMonthStart(extendedYear, month, true);
+    const int32_t nextMonthStart = handleComputeMonthStart(extendedYear, month+1, true);
+    const int32_t thisMonthStart = handleComputeMonthStart(extendedYear, month, true);
+    return nextMonthStart - thisMonthStart;
 }
 
-int32_t Calendar::handleGetYearLength(int32_t eyear) const {
-    int32_t nextYearStart = handleComputeMonthStart(eyear + 1, 0, false);
-    int32_t thisYearStart = handleComputeMonthStart(eyear, 0, false);
+int32_t Calendar::handleGetYearLength(int32_t eyear) const
+{
+    const int32_t nextYearStart = handleComputeMonthStart(eyear + 1, 0, false);
+    const int32_t thisYearStart = handleComputeMonthStart(eyear, 0, false);
     return nextYearStart - thisYearStart;
 }
 
diff --git a/icu4c/source/i18n/i18n.vcxproj b/icu4c/source/i18n/i18n.vcxproj
index a9622aa45e9..55471bef149 100644
--- a/icu4c/source/i18n/i18n.vcxproj
+++ b/icu4c/source/i18n/i18n.vcxproj
@@ -34,10 +34,7 @@
       <TypeLibraryName>$(OutDir)\icuin.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <PreprocessorDefinitions>U_ATTRIBUTE_DEPRECATED=;U_I18N_IMPLEMENTATION;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <WarningLevel>Level3</WarningLevel>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <CompileAs>Default</CompileAs>
diff --git a/icu4c/source/i18n/i18n_uwp.vcxproj b/icu4c/source/i18n/i18n_uwp.vcxproj
index f389562d058..dd997d11580 100644
--- a/icu4c/source/i18n/i18n_uwp.vcxproj
+++ b/icu4c/source/i18n/i18n_uwp.vcxproj
@@ -70,8 +70,6 @@
       <SuppressStartupBanner>true</SuppressStartupBanner>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <!-- U_DISABLE_RENAMING -->
       <!-- U_HIDE_DRAFT_API & U_HIDE_DEPRECATED_API -->
@@ -80,7 +78,6 @@
       <ExceptionHandling>
       </ExceptionHandling>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <TreatWChar_tAsBuiltInType>true</TreatWChar_tAsBuiltInType>
       <WarningLevel>Level3</WarningLevel>
       <SuppressStartupBanner>true</SuppressStartupBanner>
diff --git a/icu4c/source/io/io.vcxproj b/icu4c/source/io/io.vcxproj
index bad5d666ebd..b4b31a6d090 100644
--- a/icu4c/source/io/io.vcxproj
+++ b/icu4c/source/io/io.vcxproj
@@ -34,11 +34,8 @@
       <TypeLibraryName>$(OutDir)\icuio.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>U_IO_IMPLEMENTATION;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <WarningLevel>Level3</WarningLevel>
       <CompileAs>Default</CompileAs>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
diff --git a/icu4c/source/layoutex/layoutex.vcxproj b/icu4c/source/layoutex/layoutex.vcxproj
index 0445eeed748..41fdacec7d7 100644
--- a/icu4c/source/layoutex/layoutex.vcxproj
+++ b/icu4c/source/layoutex/layoutex.vcxproj
@@ -34,8 +34,6 @@
     <!-- Options that are common to *all* project configurations -->
   <ItemDefinitionGroup>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\include;..\common;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <PreprocessorDefinitions>U_LAYOUTEX_IMPLEMENTATION;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <WarningLevel>Level3</WarningLevel>
@@ -48,7 +46,6 @@
     <ClCompile>
       <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <PrecompiledHeaderOutputFile>.\x86\Release/layoutex.pch</PrecompiledHeaderOutputFile>
       <AssemblerListingLocation>.\x86\Release/</AssemblerListingLocation>
       <ObjectFileName>.\x86\Release/</ObjectFileName>
@@ -71,7 +68,6 @@
     </Midl>
     <ClCompile>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <PrecompiledHeaderOutputFile>.\x86\Debug/layoutex.pch</PrecompiledHeaderOutputFile>
       <AssemblerListingLocation>.\x86\Debug/</AssemblerListingLocation>
       <ObjectFileName>.\x86\Debug/</ObjectFileName>
@@ -98,7 +94,6 @@
     <ClCompile>
       <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <PrecompiledHeaderOutputFile>.\x64\Release/layoutex.pch</PrecompiledHeaderOutputFile>
       <AssemblerListingLocation>.\x64\Release/</AssemblerListingLocation>
       <ObjectFileName>.\x64\Release/</ObjectFileName>
@@ -119,7 +114,6 @@
     </Midl>
     <ClCompile>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
       <PrecompiledHeaderOutputFile>.\x64\Debug/layoutex.pch</PrecompiledHeaderOutputFile>
       <AssemblerListingLocation>.\x64\Debug/</AssemblerListingLocation>
       <ObjectFileName>.\x64\Debug/</ObjectFileName>
@@ -140,15 +134,9 @@
   <ItemGroup>
     <ClCompile Include="LXUtilities.cpp" />
     <ClCompile Include="ParagraphLayout.cpp" />
-    <ClCompile Include="playout.cpp">
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
-    </ClCompile>
-    <ClCompile Include="plruns.cpp">
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
-    </ClCompile>
-    <ClCompile Include="RunArrays.cpp">
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
-    </ClCompile>
+    <ClCompile Include="playout.cpp" />
+    <ClCompile Include="plruns.cpp" />
+    <ClCompile Include="RunArrays.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="LXUtilities.h" />
diff --git a/icu4c/source/samples/break/break.vcxproj b/icu4c/source/samples/break/break.vcxproj
index 59a93b56ed3..d9a51001d2a 100644
--- a/icu4c/source/samples/break/break.vcxproj
+++ b/icu4c/source/samples/break/break.vcxproj
@@ -33,8 +33,6 @@
   <!-- Options that are common to *all* project configurations -->
   <ItemDefinitionGroup>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\..\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <WarningLevel>Level3</WarningLevel>
     </ClCompile>
diff --git a/icu4c/source/samples/cal/cal.vcxproj b/icu4c/source/samples/cal/cal.vcxproj
index aee2c34333c..2051033546d 100644
--- a/icu4c/source/samples/cal/cal.vcxproj
+++ b/icu4c/source/samples/cal/cal.vcxproj
@@ -33,11 +33,8 @@
   <!-- Options that are common to *all* project configurations -->
   <ItemDefinitionGroup>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\..\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <WarningLevel>Level3</WarningLevel>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
     </ClCompile>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
diff --git a/icu4c/source/samples/case/case.vcxproj b/icu4c/source/samples/case/case.vcxproj
index f0c4122e48c..ab24c9344b3 100644
--- a/icu4c/source/samples/case/case.vcxproj
+++ b/icu4c/source/samples/case/case.vcxproj
@@ -33,11 +33,8 @@
   <!-- Options that are common to *all* project configurations -->
   <ItemDefinitionGroup>
     <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <AdditionalIncludeDirectories>..\..\..\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <WarningLevel>Level3</WarningLevel>
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
     </ClCompile>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
diff --git a/icu4c/source/samples/citer/citer.vcxproj b/icu4c/source/samples/citer/citer.vcxproj
index 68e4fadeb2f..c9211442449 100644
--- a/icu4c/source/samples/citer/citer.vcxproj
+++ b/icu4c/source/samples/citer/citer.vcxproj
@@ -30,12 +30,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Release|x64'">.\x64\Release\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Release|x64'">false</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <AdditionalIncludeDirectories>..\..\..\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
diff --git a/icu4c/source/samples/coll/coll.vcxproj b/icu4c/source/samples/coll/coll.vcxproj
index f58b0521715..fd49d1b8915 100644
--- a/icu4c/source/samples/coll/coll.vcxproj
+++ b/icu4c/source/samples/coll/coll.vcxproj
@@ -30,12 +30,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">.\x64\Debug\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Midl>
       <TypeLibraryName>.\x86\Release/coll.tlb</TypeLibraryName>
diff --git a/icu4c/source/samples/csdet/csdet.vcxproj b/icu4c/source/samples/csdet/csdet.vcxproj
index 74d4ad57dd1..234a7b84e68 100644
--- a/icu4c/source/samples/csdet/csdet.vcxproj
+++ b/icu4c/source/samples/csdet/csdet.vcxproj
@@ -31,12 +31,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Release|x64'">.\x64\Release\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Release|x64'">false</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <AdditionalIncludeDirectories>../../../include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
diff --git a/icu4c/source/samples/date/date.vcxproj b/icu4c/source/samples/date/date.vcxproj
index e5d34f37345..3d20f9576ed 100644
--- a/icu4c/source/samples/date/date.vcxproj
+++ b/icu4c/source/samples/date/date.vcxproj
@@ -30,12 +30,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">.\x64\Debug\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Midl>
       <TypeLibraryName>.\x86\Release/date.tlb</TypeLibraryName>
diff --git a/icu4c/source/samples/datefmt/datefmt.vcxproj b/icu4c/source/samples/datefmt/datefmt.vcxproj
index b1cf597f7b9..00dcd6d6700 100644
--- a/icu4c/source/samples/datefmt/datefmt.vcxproj
+++ b/icu4c/source/samples/datefmt/datefmt.vcxproj
@@ -30,12 +30,6 @@
     <IntDir Condition="'$(Configuration)|$(Platform)'=='Release|x64'">.\x64\Release\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Release|x64'">false</LinkIncremental>
   </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <LanguageStandard>stdcpp17</LanguageStandard>
-      <LanguageStandard_C>stdc11</LanguageStandard_C>
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   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Midl>
       <TypeLibraryName>.\x86\Debug/datefmt.tlb</TypeLibraryName>
diff --git a/icu4c/source/samples/dtitvfmtsample/dtitvfmtsample.vcxproj b/icu4c/source/samples/dtitvfmtsample/dtitvfmtsample.vcxproj
index e5fbcb88a2d..aea18b217f3 100644
--- a/icu4c/source/samples/dtitvfmtsample/dtitvfmtsample.vcxproj
+++ b/icu4c/source/samples/dtitvfmtsample/dtitvfmtsample.vcxproj
@@ -65,12 +65,6 @@
     <IntDir>.\x64\Release\</IntDir>
     <TargetName>$(ProjectName)</TargetName>
   </PropertyGroup>
-  <ItemDefinitionGroup>
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-      <LanguageStandard_C>stdc11</LanguageStandard_C>
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     <ClCompile>
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diff --git a/icu4c/source/samples/dtptngsample/dtptngsample.vcxproj b/icu4c/source/samples/dtptngsample/dtptngsample.vcxproj
index 3d01f6cb465..542b3439f03 100644
--- a/icu4c/source/samples/dtptngsample/dtptngsample.vcxproj
+++ b/icu4c/source/samples/dtptngsample/dtptngsample.vcxproj
@@ -65,12 +65,6 @@
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index 66c6053cca7..31ac1d942ef 100644
--- a/icu4c/source/samples/layout/layout.vcxproj
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@@ -30,12 +30,6 @@
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diff --git a/icu4c/source/samples/legacy/legacy.vcxproj b/icu4c/source/samples/legacy/legacy.vcxproj
index 1f7c71ac438..41f5aac4a4d 100644
--- a/icu4c/source/samples/legacy/legacy.vcxproj
+++ b/icu4c/source/samples/legacy/legacy.vcxproj
@@ -66,12 +66,6 @@
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@@ -93,6 +87,8 @@
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+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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     <ResourceCompile>
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diff --git a/icu4c/source/samples/msgfmt/msgfmt.vcxproj b/icu4c/source/samples/msgfmt/msgfmt.vcxproj
index 1123d6fb545..b1a90405b6c 100644
--- a/icu4c/source/samples/msgfmt/msgfmt.vcxproj
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diff --git a/icu4c/source/samples/numfmt/numfmt.vcxproj b/icu4c/source/samples/numfmt/numfmt.vcxproj
index 3de1f6d1edc..4ea39eb54a7 100644
--- a/icu4c/source/samples/numfmt/numfmt.vcxproj
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diff --git a/icu4c/source/samples/plurfmtsample/plurfmtsample.vcxproj b/icu4c/source/samples/plurfmtsample/plurfmtsample.vcxproj
index 1b375dbceb9..c0d3246ae82 100644
--- a/icu4c/source/samples/plurfmtsample/plurfmtsample.vcxproj
+++ b/icu4c/source/samples/plurfmtsample/plurfmtsample.vcxproj
@@ -64,12 +64,6 @@
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+    <ClCompile Include="collationtest.cpp" />
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-    <ClCompile Include="prscmnts.cpp">
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
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+    <ClCompile Include="parse.cpp" />
+    <ClCompile Include="prscmnts.cpp" />
     <ClCompile Include="rbutil.c" />
     <ClCompile Include="read.c" />
-    <ClCompile Include="reslist.cpp">
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
-    </ClCompile>
+    <ClCompile Include="reslist.cpp" />
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-    <ClCompile Include="wrtxml.cpp">
-      <DisableLanguageExtensions>false</DisableLanguageExtensions>
-    </ClCompile>
+    <ClCompile Include="wrtjava.cpp" />
+    <ClCompile Include="wrtxml.cpp" />
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   <ItemGroup>
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index 3100e190f0b..b5ddda4ca92 100644
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@@ -32,11 +32,8 @@
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index 66a25add0d1..577b84378bc 100644
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index e3044e35dcd..2277f5799fa 100644
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index 5c2051b3107..56f2070b67d 100644
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diff --git a/icu4c/source/tools/icupkg/icupkg.vcxproj b/icu4c/source/tools/icupkg/icupkg.vcxproj
index 8bbbc2ccbad..9f907ae4fee 100644
--- a/icu4c/source/tools/icupkg/icupkg.vcxproj
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index 0f5ebbc0781..cb9e9e2e91d 100644
--- a/icu4c/source/tools/icuswap/icuswap.vcxproj
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@@ -91,6 +84,8 @@
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@@ -196,7 +189,6 @@
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+    <ClCompile Include="pkg_gencmn.cpp" />
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diff --git a/icu4c/source/tools/tzcode/icuzdump.vcxproj b/icu4c/source/tools/tzcode/icuzdump.vcxproj
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--- a/icu4c/source/tools/tzcode/icuzdump.vcxproj
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@@ -75,6 +68,8 @@
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