desciptive exception when giveio is required but not installed
diff --git a/pyparallel/parallel/parallelwin32.py b/pyparallel/parallel/parallelwin32.py
index 5c287cb..5754578 100644
--- a/pyparallel/parallel/parallelwin32.py
+++ b/pyparallel/parallel/parallelwin32.py
@@ -58,7 +58,8 @@
#python extension in earlier versions of this modules
_pyparallel = ctypes.windll.simpleio
#need to initialize giveio on WinNT based systems
-_pyparallel.init()
+if _pyparallel.init():
+ raise IOError('Could not access the giveio driver which is required on NT based systems.')
class Parallel: