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+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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       <CompileAs>Default</CompileAs>
       <DisableLanguageExtensions>false</DisableLanguageExtensions>
diff --git a/icu4c/source/tools/genccode/genccode.vcxproj b/icu4c/source/tools/genccode/genccode.vcxproj
index aad028f8c710..413ba78813c5 100644
--- a/icu4c/source/tools/genccode/genccode.vcxproj
+++ b/icu4c/source/tools/genccode/genccode.vcxproj
@@ -32,6 +32,8 @@
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     </Midl>
     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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       <CompileAs>Default</CompileAs>
       <DisableLanguageExtensions>false</DisableLanguageExtensions>
diff --git a/icu4c/source/tools/gencfu/gencfu.vcxproj b/icu4c/source/tools/gencfu/gencfu.vcxproj
index 4018d5078dad..87bb4d9d632a 100644
--- a/icu4c/source/tools/gencfu/gencfu.vcxproj
+++ b/icu4c/source/tools/gencfu/gencfu.vcxproj
@@ -32,6 +32,8 @@
       <TypeLibraryName>$(OutDir)\gencfu.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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       <CompileAs>Default</CompileAs>
       <DisableLanguageExtensions>false</DisableLanguageExtensions>
diff --git a/icu4c/source/tools/gencmn/gencmn.vcxproj b/icu4c/source/tools/gencmn/gencmn.vcxproj
index 94c18b6ac52f..cdf72bc80ea4 100644
--- a/icu4c/source/tools/gencmn/gencmn.vcxproj
+++ b/icu4c/source/tools/gencmn/gencmn.vcxproj
@@ -32,9 +32,11 @@
       <TypeLibraryName>$(OutDir)/gencmn.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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       <CompileAs>Default</CompileAs>
-      <DisableLanguageExtensions>true</DisableLanguageExtensions>
+      <DisableLanguageExtensions>false</DisableLanguageExtensions>
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index 8e3b7bab4fbc..2073d99ad56f 100644
--- a/icu4c/source/tools/gencnval/gencnval.vcxproj
+++ b/icu4c/source/tools/gencnval/gencnval.vcxproj
@@ -32,6 +32,8 @@
       <TypeLibraryName>$(OutDir)/gencnval.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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       <CompileAs>Default</CompileAs>
       <DisableLanguageExtensions>false</DisableLanguageExtensions>
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index 42c1ba7869a7..87a405e74c69 100644
--- a/icu4c/source/tools/gendict/gendict.vcxproj
+++ b/icu4c/source/tools/gendict/gendict.vcxproj
@@ -32,9 +32,11 @@
       <TypeLibraryName>$(OutDir)\gendict.tlb</TypeLibraryName>
     </Midl>
     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
       <WarningLevel>Level3</WarningLevel>
       <CompileAs>Default</CompileAs>
-      <DisableLanguageExtensions>true</DisableLanguageExtensions>
+      <DisableLanguageExtensions>false</DisableLanguageExtensions>
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       <PrecompiledHeaderOutputFile>$(OutDir)\gendict.pch</PrecompiledHeaderOutputFile>
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index 2f41299098be..dcafdcda430b 100644
--- a/icu4c/source/tools/gennorm2/gennorm2.vcxproj
+++ b/icu4c/source/tools/gennorm2/gennorm2.vcxproj
@@ -47,6 +47,8 @@
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     </Midl>
     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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index f5ba9bf22f3f..833a42d8e736 100644
--- a/icu4c/source/tools/genrb/derb.vcxproj
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@@ -32,9 +32,11 @@
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     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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       <CompileAs>Default</CompileAs>
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index 66651c11d03e..d4f665be08fa 100644
--- a/icu4c/source/tools/genrb/genrb.vcxproj
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@@ -32,9 +32,11 @@
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     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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       <CompileAs>Default</CompileAs>
-      <DisableLanguageExtensions>true</DisableLanguageExtensions>
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diff --git a/icu4c/source/tools/gensprep/gensprep.vcxproj b/icu4c/source/tools/gensprep/gensprep.vcxproj
index c6f7bbd861c3..3100e190f0b1 100644
--- a/icu4c/source/tools/gensprep/gensprep.vcxproj
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@@ -32,6 +32,8 @@
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     </Midl>
     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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index 79155c11aa13..66a25add0d1b 100644
--- a/icu4c/source/tools/gentest/gentest.vcxproj
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@@ -33,9 +33,11 @@
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     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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       <CompileAs>Default</CompileAs>
-      <DisableLanguageExtensions>true</DisableLanguageExtensions>
+      <DisableLanguageExtensions>false</DisableLanguageExtensions>
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index 48b4c23cf8bd..ce10bea4497c 100644
--- a/icu4c/source/tools/icuexportdata/icuexportdata.vcxproj
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@@ -32,6 +32,8 @@
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     <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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--- a/icu4c/source/tools/icuinfo/icuinfo.vcxproj
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@@ -32,6 +32,8 @@
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index dac99beb4e5e..5c2051b31079 100644
--- a/icu4c/source/tools/icuinfo/testplug.vcxproj
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@@ -32,9 +32,11 @@
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+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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       <PreprocessorDefinitions>T_CTEST_IMPLEMENTATION;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <DisableLanguageExtensions>true</DisableLanguageExtensions>
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diff --git a/icu4c/source/tools/icupkg/icupkg.vcxproj b/icu4c/source/tools/icupkg/icupkg.vcxproj
index 7b9cf58491af..8bbbc2ccbad2 100644
--- a/icu4c/source/tools/icupkg/icupkg.vcxproj
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@@ -32,9 +32,11 @@
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     </Midl>
     <ClCompile>
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+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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-      <DisableLanguageExtensions>true</DisableLanguageExtensions>
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index 3c60511b42e3..0f5ebbc07814 100644
--- a/icu4c/source/tools/icuswap/icuswap.vcxproj
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     <IntDir Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">.\x64\Debug\</IntDir>
     <LinkIncremental Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</LinkIncremental>
   </PropertyGroup>
+  <ItemDefinitionGroup>
+    <ClCompile>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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+  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
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@@ -77,7 +83,7 @@
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-      <DisableLanguageExtensions>true</DisableLanguageExtensions>
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-      <DisableLanguageExtensions>true</DisableLanguageExtensions>
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diff --git a/icu4c/source/tools/makeconv/makeconv.vcxproj b/icu4c/source/tools/makeconv/makeconv.vcxproj
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--- a/icu4c/source/tools/makeconv/makeconv.vcxproj
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@@ -32,6 +32,8 @@
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--- a/icu4c/source/tools/pkgdata/pkgdata.vcxproj
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@@ -32,9 +32,11 @@
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+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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index 0995ef06f7eb..529a03a6e4db 100644
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   <ItemDefinitionGroup>
     <ClCompile>
-       <AdditionalIncludeDirectories>..\..\..\include;..\..\common;..\..\i18n;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <LanguageStandard>stdcpp17</LanguageStandard>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
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index 4f7b96fc2918..93bca180eb39 100644
--- a/icu4c/source/tools/tzcode/icuzdump.vcxproj
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