diff --git a/examples/scan.py b/examples/scan.py
old mode 100644
new mode 100755
index c3f1721..49be647
--- a/examples/scan.py
+++ b/examples/scan.py
@@ -1,7 +1,9 @@
-import serial
-import serial.tools.list_ports
-
-print("Serial devices available:")
-l = serial.tools.list_ports.comports()
-for ll in l:
-    print(ll.device, ll.description)
+#!/usr/bin/python
+
+import serial
+import serial.tools.list_ports
+
+print("Serial devices available:")
+l = serial.tools.list_ports.comports()
+for ll in l:
+    print(ll.device, ll.description)
diff --git a/pyfirmata2/pyfirmata2.py b/pyfirmata2/pyfirmata2.py
index d9de871..d094f18 100755
--- a/pyfirmata2/pyfirmata2.py
+++ b/pyfirmata2/pyfirmata2.py
@@ -588,7 +588,7 @@ def read(self):
         if self.mode == UNAVAILABLE:
             raise IOError("Cannot read pin {0}".format(self.__str__()))
         if (self.mode is INPUT) or (self.mode is INPUT_PULLUP) or (self.type == ANALOG):
-            warnings.warn("Use a callback handler for pin {0}".format(self.__str__()))
+            raise IOError("Reading via polling is not supported by this library. Please use the original pyfirmata.")
         return self.value
 
     def register_callback(self, _callback):
diff --git a/setup.py b/setup.py
index 46ae247..59448cc 100755
--- a/setup.py
+++ b/setup.py
@@ -7,7 +7,7 @@
 
 setup(
     name='pyFirmata2',
-    version='2.4.6',
+    version='2.5.0',
     description="Use your Arduino as a data acquisition card under Python",
     long_description=long_description,
     author='Bernd Porr',