diff --git a/platforms/posix/src/px4/windows/runtime/init.cpp b/platforms/posix/src/px4/windows/runtime/init.cpp
index d2cd8592fc..22cde7cbfa 100644
--- a/platforms/posix/src/px4/windows/runtime/init.cpp
+++ b/platforms/posix/src/px4/windows/runtime/init.cpp
@@ -54,7 +54,13 @@
 // the default ~15.6 ms HPET tick, which throttles SITL sim time to
 // ~40 % of wall time. Requesting 1 ms resolution drops the floor to
 // the documented minimum.
+// Older MinGW-w64 headers (<= 8.0) ship the prototypes via <mmsystem.h>
+// instead of the split <timeapi.h> introduced in newer SDKs.
+#if defined(__MINGW32__) && (__MINGW64_VERSION_MAJOR < 9)
+#include <mmsystem.h>
+#else
 #include <timeapi.h>
+#endif
 
 // CREATE_WAITABLE_TIMER_HIGH_RESOLUTION (Windows 10 1803+, build 17134)
 // may not be defined in older SDK headers. Mirror the literal values