diff -r a375e31bf312 -r c1298e7ffe3a targets/Win32/plc_Win32_main.c
--- a/targets/Win32/plc_Win32_main.c	Sun Mar 05 00:38:25 2017 +0000
+++ b/targets/Win32/plc_Win32_main.c	Fri Mar 24 12:07:47 2017 +0000
@@ -84,7 +84,7 @@
     if (debug_sem == NULL)
     {
         printf("startPLC CreateSemaphore debug_sem error: %d\n", GetLastError());
-        return;
+        return 1;
     }
 
     debug_wait_sem = CreateSemaphore(
@@ -96,7 +96,7 @@
     if (debug_wait_sem == NULL)
     {
         printf("startPLC CreateSemaphore debug_wait_sem error: %d\n", GetLastError());
-        return;
+        return 1;
     }
 
     python_sem = CreateSemaphore(
@@ -108,7 +108,7 @@
     if (python_sem == NULL)
     {
         printf("startPLC CreateSemaphore python_sem error: %d\n", GetLastError());
-        return;
+        return 1;
     }
     python_wait_sem = CreateSemaphore(
                             NULL,           // default security attributes
@@ -120,7 +120,7 @@
     if (python_wait_sem == NULL)
     {
         printf("startPLC CreateSemaphore python_wait_sem error: %d\n", GetLastError());
-        return;
+        return 1;
     }