diff --git a/testgui/testgui.vcproj b/testgui/testgui.vcproj
index 0d0db8d..0f73a01 100644
--- a/testgui/testgui.vcproj
+++ b/testgui/testgui.vcproj
@@ -183,7 +183,7 @@
 			UniqueIdentifier="{4FC737F1-C7A5-4376-A066-2A32D752A2FF}"
 			>
 			<File
-				RelativePath="..\windows\hid.cpp"
+				RelativePath="..\windows\hid.c"
 				>
 			</File>
 			<File
diff --git a/windows/Makefile.mingw b/windows/Makefile.mingw
index 70181e1..3f13386 100644
--- a/windows/Makefile.mingw
+++ b/windows/Makefile.mingw
@@ -10,8 +10,8 @@ all: hidtest
 
 CC=gcc
 CXX=g++
-COBJS=
-CPPOBJS=../hidtest/hidtest.o hid.o
+COBJS=hid.o
+CPPOBJS=../hidtest/hidtest.o
 OBJS=$(COBJS) $(CPPOBJS)
 CFLAGS=-I../hidapi -g -c
 LIBS= -lsetupapi
diff --git a/windows/ddk_build/sources b/windows/ddk_build/sources
index 3314465..7f06a09 100644
--- a/windows/ddk_build/sources
+++ b/windows/ddk_build/sources
@@ -13,7 +13,7 @@ TARGETLIBS=$(SDK_LIB_PATH)\hid.lib \
 USE_MSVCRT=1
 
 INCLUDES= ..\..\hidapi
-SOURCES= ..\hid.cpp \
+SOURCES= ..\hid.c \
 
 
 TARGET_DESTINATION=retail
diff --git a/windows/hid.cpp b/windows/hid.c
similarity index 100%
rename from windows/hid.cpp
rename to windows/hid.c
diff --git a/windows/hidapi.vcproj b/windows/hidapi.vcproj
index 8e6f991..ee9569c 100644
--- a/windows/hidapi.vcproj
+++ b/windows/hidapi.vcproj
@@ -175,7 +175,7 @@
 			UniqueIdentifier="{4FC737F1-C7A5-4376-A066-2A32D752A2FF}"
 			>
 			<File
-				RelativePath=".\hid.cpp"
+				RelativePath=".\hid.c"
 				>
 			</File>
 		</Filter>