diff --git a/desmume/src/windows/IORegView.c b/desmume/src/windows/IORegView.c
index 7a7e79b99..31acf81bb 100644
--- a/desmume/src/windows/IORegView.c
+++ b/desmume/src/windows/IORegView.c
@@ -32,7 +32,6 @@ LRESULT Ioreg_OnPaint(HWND hwnd, WPARAM wParam, LPARAM lParam)
         HDC          hdc;
         PAINTSTRUCT  ps;
         TCHAR        text[80];
-//        NDS_header * header = nds.getROMHeader();
         
         hdc = BeginPaint(hwnd, &ps);
         
@@ -73,7 +72,8 @@ BOOL CALLBACK IoregView_Proc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lPa
                  return 1;
             case WM_CLOSE :
                  CWindow_RemoveFromRefreshList(win);
-                 free(win);
+                 if (win)
+                    free(win);
                  EndDialog(hwnd, 0);
                  return 1;
             case WM_PAINT:
@@ -84,7 +84,8 @@ BOOL CALLBACK IoregView_Proc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lPa
                  {
                         case IDC_FERMER :
                              CWindow_RemoveFromRefreshList(win);
-                             free(win);
+                             if (win)
+                                free(win);
                              EndDialog(hwnd, 0);
                              return 1;
                  }
diff --git a/desmume/src/windows/main.c b/desmume/src/windows/main.c
index 2ffbf7969..950894e2e 100644
--- a/desmume/src/windows/main.c
+++ b/desmume/src/windows/main.c
@@ -778,10 +778,16 @@ LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM
                   return 0;
                   case IDM_IOREG:
                        {
-                            cwindow_struct IoregView;
+                            cwindow_struct *IoregView;
 
-                            if (CWindow_Init2(&IoregView, hAppInst, HWND_DESKTOP, "IO REG VIEW", IDD_IO_REG, IoregView_Proc) == 0)
-                               CWindow_Show(&IoregView);
+                            if ((IoregView = malloc(sizeof(cwindow_struct))) == NULL)
+                               return 0;
+
+                            if (CWindow_Init2(IoregView, hAppInst, HWND_DESKTOP, "IO REG VIEW", IDD_IO_REG, IoregView_Proc) == 0)
+                            {
+                               CWindow_AddToRefreshList(IoregView);
+                               CWindow_Show(IoregView);
+                            }
                        }
                   return 0;
                   case IDM_QUIT: