diff --git a/include/iini.h b/include/iini.h
index 1c52d09..12a86b7 100644
--- a/include/iini.h
+++ b/include/iini.h
@@ -6,8 +6,12 @@
 #include <assert.h>
 #include "sysenv.h"
 #if _OS_WIN
+#ifndef strcasecmp
 #define strcasecmp _stricmp
+#endif
+#ifndef strncasecmp
 #define strncasecmp _strnicmp
+#endif
 #elif _OS_LINUX
 #include <strings.h>
 #else
diff --git a/include/ssocket.h b/include/ssocket.h
index 8b69ce0..eb1e146 100644
--- a/include/ssocket.h
+++ b/include/ssocket.h
@@ -18,8 +18,12 @@
 #include <Winsock2.h>
 #include <Ws2tcpip.h>
 #include <CoreWindow.h>
+#ifndef strcasecmp
 #define strcasecmp _stricmp
+#endif
+#ifndef strncasecmp
 #define strncasecmp _strnicmp
+#endif
 //#define socklen_t int
 #elif LINUX_PART
 #include <unistd.h>