diff --git a/OMCompiler/Compiler/Util/System.mo b/OMCompiler/Compiler/Util/System.mo
index 94bb585091e..2b9c19d00f1 100644
--- a/OMCompiler/Compiler/Util/System.mo
+++ b/OMCompiler/Compiler/Util/System.mo
@@ -1119,7 +1119,7 @@ public function fileContentsEqual
   external "C" result = SystemImpl__fileContentsEqual(file1,file2) annotation(Library = {"omcruntime"});
 end fileContentsEqual;
 
-public function rename
+public function rename "returns true if success, false otherwise"
   input String source;
   input String dest;
   output Boolean result;
diff --git a/OMCompiler/Compiler/runtime/systemimpl.c b/OMCompiler/Compiler/runtime/systemimpl.c
index 1cc6e031a68..0f7118aae7e 100644
--- a/OMCompiler/Compiler/runtime/systemimpl.c
+++ b/OMCompiler/Compiler/runtime/systemimpl.c
@@ -2995,7 +2995,7 @@ int SystemImpl__fileContentsEqual(const char *file1, const char *file2)
 
 int SystemImpl__rename(const char *source, const char *dest)
 {
-   return omc_rename(source, dest);
+   return (0 == omc_rename(source, dest));
 }
 
 char* SystemImpl__ctime(double time)
diff --git a/OMCompiler/SimulationRuntime/c/util/omc_file.c b/OMCompiler/SimulationRuntime/c/util/omc_file.c
index 36d85c6838d..29300b3c64f 100644
--- a/OMCompiler/SimulationRuntime/c/util/omc_file.c
+++ b/OMCompiler/SimulationRuntime/c/util/omc_file.c
@@ -240,11 +240,16 @@ int omc_unlink(const char *filename) {
   return result;
 }
 
+// zero on success, anything else on failure!
 int omc_rename(const char *source, const char *dest) {
 #if defined(__MINGW32__) || defined(_MSC_VER)
-  return MoveFileEx(source, dest, MOVEFILE_REPLACE_EXISTING);
+  // If the function succeeds, the return value is nonzero.
+  // If the function fails, the return value is zero (0). To get extended error information, call GetLastError.
+  return !MoveFileEx(source, dest, MOVEFILE_REPLACE_EXISTING);
 #endif
-  return 0==rename(source,dest);
+  // On success, zero is returned.  On error, -1 is returned, and
+  // errno is set to indicate the error.
+  return rename(source,dest);
 }
 
 #if defined(__MINGW32__) || defined(_MSC_VER)