Index: win32_api.hpp
===================================================================
--- win32_api.hpp	(revision 852)
+++ win32_api.hpp	(revision 853)
@@ -1472,6 +1472,7 @@
             )
          )
       {
+	     CoUninitialize();
          return false;
       }
  
@@ -1489,6 +1490,7 @@
       {
          pIWbemLocator->Release();
  
+		 CoUninitialize();
          return false;
       }
  
@@ -1510,6 +1512,7 @@
          pIWbemLocator->Release();
          pWbemServices->Release();
  
+		 CoUninitialize();
          return false;
       }
       
@@ -1522,26 +1525,37 @@
          pWbemServices->Release();
          pEnumObject->Release();
  
+         CoUninitialize();
          return false;
       }
 
       wchar_variant vwchar;
 
-      while( 0 == pEnumObject->Next( WBEM_INFINITE_IG, uCount, &pClassObject, &uReturned ) )
-      {
-         if ( 0 == pClassObject->Get( L"LastBootUpTime", 0, &vwchar, 0, 0 ) )
-         {
-            bRet = true;
-             strValue = vwchar.value.pbstrVal;
-             VariantClear(&vwchar );
-             break;
-         }
-      }
+	  while( 0 == pEnumObject->Next( WBEM_INFINITE_IG, uCount, &pClassObject, &uReturned ) )
+	  {
+		if (pClassObject != 0)
+		{
+			if ( 0 == pClassObject->Get( L"LastBootUpTime", 0, &vwchar, 0, 0 ) )
+			{
+				bRet = true;
+				strValue = vwchar.value.pbstrVal;
+				VariantClear(&vwchar );
+				break;
+			}
+		}
+	  }
  
-      pIWbemLocator->Release();
-      pWbemServices->Release();
-      pEnumObject->Release();
-      pClassObject->Release();
+      if (pIWbemLocator != 0) 
+          pIWbemLocator->Release();
+
+      if (pWbemServices != 0) 
+          pWbemServices->Release();
+
+      if (pEnumObject != 0)
+          pEnumObject->Release();
+
+      if (pClassObject != 0)
+          pClassObject->Release();
    }
  
    CoUninitialize();