diff --git a/src/syncterm/SyncTERM.vcxproj b/src/syncterm/SyncTERM.vcxproj
index fe5ed0ddf9383b67248c9d5283722e830b0a5aaf..947a1b182492af9723686e0329e0ed3401de9354 100644
--- a/src/syncterm/SyncTERM.vcxproj
+++ b/src/syncterm/SyncTERM.vcxproj
@@ -79,6 +79,7 @@
       <PreprocessorDefinitions>WIN32;TELNET_NO_DLL;_DEBUG;_WINDOWS;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>%(AdditionalIncludeDirectories);..\sbbs3</AdditionalIncludeDirectories>
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <LanguageStandard>stdc17</LanguageStandard>
       <LanguageStandard_C>stdc17</LanguageStandard_C>
     </ClCompile>
     <Link>
@@ -98,6 +99,7 @@
       <PreprocessorDefinitions>WIN32;TELNET_NO_DLL;NDEBUG;_WINDOWS;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>%(AdditionalIncludeDirectories);..\sbbs3;</AdditionalIncludeDirectories>
       <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
+      <LanguageStandard>stdc17</LanguageStandard>
       <LanguageStandard_C>stdc17</LanguageStandard_C>
     </ClCompile>
     <Link>