diff --git a/assignment-client/src/AssignmentClientApp.cpp b/assignment-client/src/AssignmentClientApp.cpp
index fef2a3139d..4acb52f2f2 100644
--- a/assignment-client/src/AssignmentClientApp.cpp
+++ b/assignment-client/src/AssignmentClientApp.cpp
@@ -34,16 +34,16 @@
 AssignmentClientApp::AssignmentClientApp(int argc, char* argv[]) :
     QCoreApplication(argc, argv)
 {
-#   ifndef WIN32
+#ifndef _WIN32
     setvbuf(stdout, NULL, _IOLBF, 0);
-#   endif
+#endif
 
     // setup a shutdown event listener to handle SIGTERM or WM_CLOSE for us
-#   ifdef _WIN32
+#ifdef _WIN32
     installNativeEventFilter(&ShutdownEventListener::getInstance());
-#   else
+#else
     ShutdownEventListener::getInstance();
-#   endif
+#endif
 
     // parse command-line
     QCommandLineParser parser;
diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index c5951a2aff..ae4944b4ac 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -7345,7 +7345,7 @@ void Application::updateWindowTitle() const {
 
     QString title = currentPlaceName + connectionStatus + metaverseDetails + domainDetails + buildVersion;
 
-#ifndef WIN32
+#ifndef _WIN32
     // crashes with vs2013/win32
     qCDebug(interfaceapp, "Application title set to: %s", title.toStdString().c_str());
 #endif
diff --git a/libraries/audio-client/src/AudioClient.cpp b/libraries/audio-client/src/AudioClient.cpp
index 16b217bc53..41b7350c2a 100644
--- a/libraries/audio-client/src/AudioClient.cpp
+++ b/libraries/audio-client/src/AudioClient.cpp
@@ -26,7 +26,7 @@
 #include <CoreAudio/AudioHardware.h>
 #endif
 
-#ifdef WIN32
+#ifdef _WIN32
 #ifndef WIN32_LEAN_AND_MEAN
 #define WIN32_LEAN_AND_MEAN 1
 #endif
@@ -573,7 +573,7 @@ QString defaultAudioDeviceName(QAudio::Mode mode) {
         }
     }
 #endif
-#ifdef WIN32
+#ifdef _WIN32
     //Check for Windows Vista or higher, IMMDeviceEnumerator doesn't work below that.
     if (!IsWindowsVistaOrGreater()) { // lower then vista
         if (mode == QAudio::AudioInput) {
diff --git a/libraries/networking/src/Assignment.cpp b/libraries/networking/src/Assignment.cpp
index 2d1dedc003..43468c36dc 100644
--- a/libraries/networking/src/Assignment.cpp
+++ b/libraries/networking/src/Assignment.cpp
@@ -96,7 +96,7 @@ Assignment::Assignment(ReceivedMessage& message) :
     packetStream >> *this;
 }
 
-#ifdef WIN32
+#ifdef _WIN32
 #pragma warning(default:4351)
 #endif
 
diff --git a/libraries/networking/src/udt/Socket.cpp b/libraries/networking/src/udt/Socket.cpp
index eeed277875..214ed38379 100644
--- a/libraries/networking/src/udt/Socket.cpp
+++ b/libraries/networking/src/udt/Socket.cpp
@@ -32,7 +32,7 @@
 
 using namespace udt;
 
-#ifdef WIN32
+#ifdef _WIN32
 #include <winsock2.h>
 #include <WS2tcpip.h>
 #else
@@ -260,7 +260,7 @@ qint64 Socket::writeDatagram(const QByteArray& datagram, const SockAddr& sockAdd
     if (bytesWritten < 0 || pending) {
         int wsaError = 0;
         static std::atomic<int> previousWsaError (0);
-#ifdef WIN32
+#ifdef _WIN32
         wsaError = WSAGetLastError();
 #endif
         QString errorString;
@@ -554,7 +554,7 @@ std::vector<SockAddr> Socket::getConnectionSockAddrs() {
 void Socket::handleSocketError(SocketType socketType, QAbstractSocket::SocketError socketError) {
     int wsaError = 0;
     static std::atomic<int> previousWsaError(0);
-#ifdef WIN32
+#ifdef _WIN32
     wsaError = WSAGetLastError();
 #endif
     int pending = _networkSocket.bytesToWrite(socketType);
diff --git a/libraries/shared/src/SharedUtil.cpp b/libraries/shared/src/SharedUtil.cpp
index 045f0a68c8..2ad32d7028 100644
--- a/libraries/shared/src/SharedUtil.cpp
+++ b/libraries/shared/src/SharedUtil.cpp
@@ -1150,7 +1150,7 @@ void setupHifiApplication(QString applicationName) {
     // You can find more details as to why this is important in the SharedUtil.h/cpp files
     setupGlobalInstances();
 
-#ifndef WIN32
+#ifndef _WIN32
     // Windows tends to hold onto log lines until it has a sizeable buffer
     // This makes the log feel unresponsive and trap useful log data in the log buffer
     // when a crash occurs.
diff --git a/libraries/shared/src/windowshacks.h b/libraries/shared/src/windowshacks.h
index e85a6f1237..3e297f230f 100644
--- a/libraries/shared/src/windowshacks.h
+++ b/libraries/shared/src/windowshacks.h
@@ -14,7 +14,7 @@
 #ifndef hifi_windowshacks_h
 #define hifi_windowshacks_h
 
-#ifdef WIN32
+#ifdef _WIN32
 
 #include <cmath>
 inline double roundf(double value) {
@@ -57,10 +57,10 @@ inline int c99_snprintf(char* str, size_t size, const char* format, ...) {
 #include <winsock2.h>
 #include <WS2tcpip.h>
 
-#else // WIN32
+#else // _WIN32
 
 #include <netinet/in.h>
 
-#endif // WIN32
+#endif // _WIN32
 
 #endif // hifi_windowshacks_h