diff --git a/CMakeLists.txt b/CMakeLists.txt
index e3a1da06656..5a0ff52b7a3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1014,7 +1014,7 @@ add_library(grpc
   src/core/lib/iomgr/socket_utils_linux.cc
   src/core/lib/iomgr/socket_utils_posix.cc
   src/core/lib/iomgr/socket_utils_uv.cc
-  src/core/lib/iomgr/socket_utils_windows.cc
+  src/core/lib/iomgr/socket_utils_windows.c
   src/core/lib/iomgr/socket_windows.cc
   src/core/lib/iomgr/tcp_client_posix.cc
   src/core/lib/iomgr/tcp_client_uv.cc
@@ -1363,7 +1363,7 @@ add_library(grpc_cronet
   src/core/lib/iomgr/socket_utils_linux.cc
   src/core/lib/iomgr/socket_utils_posix.cc
   src/core/lib/iomgr/socket_utils_uv.cc
-  src/core/lib/iomgr/socket_utils_windows.cc
+  src/core/lib/iomgr/socket_utils_windows.c
   src/core/lib/iomgr/socket_windows.cc
   src/core/lib/iomgr/tcp_client_posix.cc
   src/core/lib/iomgr/tcp_client_uv.cc
@@ -1680,7 +1680,7 @@ add_library(grpc_test_util
   src/core/lib/iomgr/socket_utils_linux.cc
   src/core/lib/iomgr/socket_utils_posix.cc
   src/core/lib/iomgr/socket_utils_uv.cc
-  src/core/lib/iomgr/socket_utils_windows.cc
+  src/core/lib/iomgr/socket_utils_windows.c
   src/core/lib/iomgr/socket_windows.cc
   src/core/lib/iomgr/tcp_client_posix.cc
   src/core/lib/iomgr/tcp_client_uv.cc
@@ -1941,7 +1941,7 @@ add_library(grpc_test_util_unsecure
   src/core/lib/iomgr/socket_utils_linux.cc
   src/core/lib/iomgr/socket_utils_posix.cc
   src/core/lib/iomgr/socket_utils_uv.cc
-  src/core/lib/iomgr/socket_utils_windows.cc
+  src/core/lib/iomgr/socket_utils_windows.c
   src/core/lib/iomgr/socket_windows.cc
   src/core/lib/iomgr/tcp_client_posix.cc
   src/core/lib/iomgr/tcp_client_uv.cc
@@ -2188,7 +2188,7 @@ add_library(grpc_unsecure
   src/core/lib/iomgr/socket_utils_linux.cc
   src/core/lib/iomgr/socket_utils_posix.cc
   src/core/lib/iomgr/socket_utils_uv.cc
-  src/core/lib/iomgr/socket_utils_windows.cc
+  src/core/lib/iomgr/socket_utils_windows.c
   src/core/lib/iomgr/socket_windows.cc
   src/core/lib/iomgr/tcp_client_posix.cc
   src/core/lib/iomgr/tcp_client_uv.cc
@@ -2943,7 +2943,7 @@ add_library(grpc++_cronet
   src/core/lib/iomgr/socket_utils_linux.cc
   src/core/lib/iomgr/socket_utils_posix.cc
   src/core/lib/iomgr/socket_utils_uv.cc
-  src/core/lib/iomgr/socket_utils_windows.cc
+  src/core/lib/iomgr/socket_utils_windows.c
   src/core/lib/iomgr/socket_windows.cc
   src/core/lib/iomgr/tcp_client_posix.cc
   src/core/lib/iomgr/tcp_client_uv.cc
diff --git a/Makefile b/Makefile
index 9a871b77020..06a91e61289 100644
--- a/Makefile
+++ b/Makefile
@@ -3005,7 +3005,7 @@ LIBGRPC_SRC = \
     src/core/lib/iomgr/socket_utils_linux.cc \
     src/core/lib/iomgr/socket_utils_posix.cc \
     src/core/lib/iomgr/socket_utils_uv.cc \
-    src/core/lib/iomgr/socket_utils_windows.cc \
+    src/core/lib/iomgr/socket_utils_windows.c \
     src/core/lib/iomgr/socket_windows.cc \
     src/core/lib/iomgr/tcp_client_posix.cc \
     src/core/lib/iomgr/tcp_client_uv.cc \
@@ -3354,7 +3354,7 @@ LIBGRPC_CRONET_SRC = \
     src/core/lib/iomgr/socket_utils_linux.cc \
     src/core/lib/iomgr/socket_utils_posix.cc \
     src/core/lib/iomgr/socket_utils_uv.cc \
-    src/core/lib/iomgr/socket_utils_windows.cc \
+    src/core/lib/iomgr/socket_utils_windows.c \
     src/core/lib/iomgr/socket_windows.cc \
     src/core/lib/iomgr/tcp_client_posix.cc \
     src/core/lib/iomgr/tcp_client_uv.cc \
@@ -3670,7 +3670,7 @@ LIBGRPC_TEST_UTIL_SRC = \
     src/core/lib/iomgr/socket_utils_linux.cc \
     src/core/lib/iomgr/socket_utils_posix.cc \
     src/core/lib/iomgr/socket_utils_uv.cc \
-    src/core/lib/iomgr/socket_utils_windows.cc \
+    src/core/lib/iomgr/socket_utils_windows.c \
     src/core/lib/iomgr/socket_windows.cc \
     src/core/lib/iomgr/tcp_client_posix.cc \
     src/core/lib/iomgr/tcp_client_uv.cc \
@@ -3922,7 +3922,7 @@ LIBGRPC_TEST_UTIL_UNSECURE_SRC = \
     src/core/lib/iomgr/socket_utils_linux.cc \
     src/core/lib/iomgr/socket_utils_posix.cc \
     src/core/lib/iomgr/socket_utils_uv.cc \
-    src/core/lib/iomgr/socket_utils_windows.cc \
+    src/core/lib/iomgr/socket_utils_windows.c \
     src/core/lib/iomgr/socket_windows.cc \
     src/core/lib/iomgr/tcp_client_posix.cc \
     src/core/lib/iomgr/tcp_client_uv.cc \
@@ -4147,7 +4147,7 @@ LIBGRPC_UNSECURE_SRC = \
     src/core/lib/iomgr/socket_utils_linux.cc \
     src/core/lib/iomgr/socket_utils_posix.cc \
     src/core/lib/iomgr/socket_utils_uv.cc \
-    src/core/lib/iomgr/socket_utils_windows.cc \
+    src/core/lib/iomgr/socket_utils_windows.c \
     src/core/lib/iomgr/socket_windows.cc \
     src/core/lib/iomgr/tcp_client_posix.cc \
     src/core/lib/iomgr/tcp_client_uv.cc \
@@ -4885,7 +4885,7 @@ LIBGRPC++_CRONET_SRC = \
     src/core/lib/iomgr/socket_utils_linux.cc \
     src/core/lib/iomgr/socket_utils_posix.cc \
     src/core/lib/iomgr/socket_utils_uv.cc \
-    src/core/lib/iomgr/socket_utils_windows.cc \
+    src/core/lib/iomgr/socket_utils_windows.c \
     src/core/lib/iomgr/socket_windows.cc \
     src/core/lib/iomgr/tcp_client_posix.cc \
     src/core/lib/iomgr/tcp_client_uv.cc \
diff --git a/binding.gyp b/binding.gyp
index 889b563e39c..317b234f325 100644
--- a/binding.gyp
+++ b/binding.gyp
@@ -716,7 +716,7 @@
         'src/core/lib/iomgr/socket_utils_linux.cc',
         'src/core/lib/iomgr/socket_utils_posix.cc',
         'src/core/lib/iomgr/socket_utils_uv.cc',
-        'src/core/lib/iomgr/socket_utils_windows.cc',
+        'src/core/lib/iomgr/socket_utils_windows.c',
         'src/core/lib/iomgr/socket_windows.cc',
         'src/core/lib/iomgr/tcp_client_posix.cc',
         'src/core/lib/iomgr/tcp_client_uv.cc',
diff --git a/config.m4 b/config.m4
index 5450bbeb1db..424c8600de5 100644
--- a/config.m4
+++ b/config.m4
@@ -145,7 +145,7 @@ if test "$PHP_GRPC" != "no"; then
     src/core/lib/iomgr/socket_utils_linux.cc \
     src/core/lib/iomgr/socket_utils_posix.cc \
     src/core/lib/iomgr/socket_utils_uv.cc \
-    src/core/lib/iomgr/socket_utils_windows.cc \
+    src/core/lib/iomgr/socket_utils_windows.c \
     src/core/lib/iomgr/socket_windows.cc \
     src/core/lib/iomgr/tcp_client_posix.cc \
     src/core/lib/iomgr/tcp_client_uv.cc \
diff --git a/config.w32 b/config.w32
index 62b8dcdd767..579c6d50267 100644
--- a/config.w32
+++ b/config.w32
@@ -122,7 +122,7 @@ if (PHP_GRPC != "no") {
     "src\\core\\lib\\iomgr\\socket_utils_linux.cc " +
     "src\\core\\lib\\iomgr\\socket_utils_posix.cc " +
     "src\\core\\lib\\iomgr\\socket_utils_uv.cc " +
-    "src\\core\\lib\\iomgr\\socket_utils_windows.cc " +
+    "src\\core\\lib\\iomgr\\socket_utils_windows.c " +
     "src\\core\\lib\\iomgr\\socket_windows.cc " +
     "src\\core\\lib\\iomgr\\tcp_client_posix.cc " +
     "src\\core\\lib\\iomgr\\tcp_client_uv.cc " +
diff --git a/gRPC-Core.podspec b/gRPC-Core.podspec
index e831058ee16..a9df0a57a47 100644
--- a/gRPC-Core.podspec
+++ b/gRPC-Core.podspec
@@ -530,7 +530,7 @@ Pod::Spec.new do |s|
                       'src/core/lib/iomgr/socket_utils_linux.cc',
                       'src/core/lib/iomgr/socket_utils_posix.cc',
                       'src/core/lib/iomgr/socket_utils_uv.cc',
-                      'src/core/lib/iomgr/socket_utils_windows.cc',
+                      'src/core/lib/iomgr/socket_utils_windows.c',
                       'src/core/lib/iomgr/socket_windows.cc',
                       'src/core/lib/iomgr/tcp_client_posix.cc',
                       'src/core/lib/iomgr/tcp_client_uv.cc',
diff --git a/grpc.gemspec b/grpc.gemspec
index 98bdbe10e12..1fda0a64c8d 100644
--- a/grpc.gemspec
+++ b/grpc.gemspec
@@ -467,7 +467,7 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/lib/iomgr/socket_utils_linux.cc )
   s.files += %w( src/core/lib/iomgr/socket_utils_posix.cc )
   s.files += %w( src/core/lib/iomgr/socket_utils_uv.cc )
-  s.files += %w( src/core/lib/iomgr/socket_utils_windows.cc )
+  s.files += %w( src/core/lib/iomgr/socket_utils_windows.c )
   s.files += %w( src/core/lib/iomgr/socket_windows.cc )
   s.files += %w( src/core/lib/iomgr/tcp_client_posix.cc )
   s.files += %w( src/core/lib/iomgr/tcp_client_uv.cc )
diff --git a/grpc.gyp b/grpc.gyp
index 55853a65c96..8c8a25beb77 100644
--- a/grpc.gyp
+++ b/grpc.gyp
@@ -282,7 +282,7 @@
         'src/core/lib/iomgr/socket_utils_linux.cc',
         'src/core/lib/iomgr/socket_utils_posix.cc',
         'src/core/lib/iomgr/socket_utils_uv.cc',
-        'src/core/lib/iomgr/socket_utils_windows.cc',
+        'src/core/lib/iomgr/socket_utils_windows.c',
         'src/core/lib/iomgr/socket_windows.cc',
         'src/core/lib/iomgr/tcp_client_posix.cc',
         'src/core/lib/iomgr/tcp_client_uv.cc',
@@ -581,7 +581,7 @@
         'src/core/lib/iomgr/socket_utils_linux.cc',
         'src/core/lib/iomgr/socket_utils_posix.cc',
         'src/core/lib/iomgr/socket_utils_uv.cc',
-        'src/core/lib/iomgr/socket_utils_windows.cc',
+        'src/core/lib/iomgr/socket_utils_windows.c',
         'src/core/lib/iomgr/socket_windows.cc',
         'src/core/lib/iomgr/tcp_client_posix.cc',
         'src/core/lib/iomgr/tcp_client_uv.cc',
@@ -785,7 +785,7 @@
         'src/core/lib/iomgr/socket_utils_linux.cc',
         'src/core/lib/iomgr/socket_utils_posix.cc',
         'src/core/lib/iomgr/socket_utils_uv.cc',
-        'src/core/lib/iomgr/socket_utils_windows.cc',
+        'src/core/lib/iomgr/socket_utils_windows.c',
         'src/core/lib/iomgr/socket_windows.cc',
         'src/core/lib/iomgr/tcp_client_posix.cc',
         'src/core/lib/iomgr/tcp_client_uv.cc',
@@ -974,7 +974,7 @@
         'src/core/lib/iomgr/socket_utils_linux.cc',
         'src/core/lib/iomgr/socket_utils_posix.cc',
         'src/core/lib/iomgr/socket_utils_uv.cc',
-        'src/core/lib/iomgr/socket_utils_windows.cc',
+        'src/core/lib/iomgr/socket_utils_windows.c',
         'src/core/lib/iomgr/socket_windows.cc',
         'src/core/lib/iomgr/tcp_client_posix.cc',
         'src/core/lib/iomgr/tcp_client_uv.cc',
diff --git a/package.xml b/package.xml
index 0656c457d23..99bcc7abf0e 100644
--- a/package.xml
+++ b/package.xml
@@ -479,7 +479,7 @@
     <file baseinstalldir="/" name="src/core/lib/iomgr/socket_utils_linux.cc" role="src" />
     <file baseinstalldir="/" name="src/core/lib/iomgr/socket_utils_posix.cc" role="src" />
     <file baseinstalldir="/" name="src/core/lib/iomgr/socket_utils_uv.cc" role="src" />
-    <file baseinstalldir="/" name="src/core/lib/iomgr/socket_utils_windows.cc" role="src" />
+    <file baseinstalldir="/" name="src/core/lib/iomgr/socket_utils_windows.c" role="src" />
     <file baseinstalldir="/" name="src/core/lib/iomgr/socket_windows.cc" role="src" />
     <file baseinstalldir="/" name="src/core/lib/iomgr/tcp_client_posix.cc" role="src" />
     <file baseinstalldir="/" name="src/core/lib/iomgr/tcp_client_uv.cc" role="src" />
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index 2955d16be68..8fece7e7652 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -121,7 +121,7 @@ CORE_SOURCE_FILES = [
   'src/core/lib/iomgr/socket_utils_linux.cc',
   'src/core/lib/iomgr/socket_utils_posix.cc',
   'src/core/lib/iomgr/socket_utils_uv.cc',
-  'src/core/lib/iomgr/socket_utils_windows.cc',
+  'src/core/lib/iomgr/socket_utils_windows.c',
   'src/core/lib/iomgr/socket_windows.cc',
   'src/core/lib/iomgr/tcp_client_posix.cc',
   'src/core/lib/iomgr/tcp_client_uv.cc',
diff --git a/tools/doxygen/Doxyfile.core.internal b/tools/doxygen/Doxyfile.core.internal
index d4c645e728a..d056e0157b4 100644
--- a/tools/doxygen/Doxyfile.core.internal
+++ b/tools/doxygen/Doxyfile.core.internal
@@ -1180,7 +1180,7 @@ src/core/lib/iomgr/socket_utils_linux.cc \
 src/core/lib/iomgr/socket_utils_posix.cc \
 src/core/lib/iomgr/socket_utils_posix.h \
 src/core/lib/iomgr/socket_utils_uv.cc \
-src/core/lib/iomgr/socket_utils_windows.cc \
+src/core/lib/iomgr/socket_utils_windows.c \
 src/core/lib/iomgr/socket_windows.cc \
 src/core/lib/iomgr/socket_windows.h \
 src/core/lib/iomgr/sys_epoll_wrapper.h \
diff --git a/tools/run_tests/generated/sources_and_headers.json b/tools/run_tests/generated/sources_and_headers.json
index b23c5d7bc91..dd962b91d4e 100644
--- a/tools/run_tests/generated/sources_and_headers.json
+++ b/tools/run_tests/generated/sources_and_headers.json
@@ -8056,7 +8056,7 @@
       "src/core/lib/iomgr/socket_utils_linux.cc", 
       "src/core/lib/iomgr/socket_utils_posix.cc", 
       "src/core/lib/iomgr/socket_utils_uv.cc", 
-      "src/core/lib/iomgr/socket_utils_windows.cc", 
+      "src/core/lib/iomgr/socket_utils_windows.c", 
       "src/core/lib/iomgr/socket_windows.cc", 
       "src/core/lib/iomgr/tcp_client_posix.cc", 
       "src/core/lib/iomgr/tcp_client_uv.cc",