diff --git a/ctypes_generation/generate.py b/ctypes_generation/generate.py
index 3786fba..50f3e42 100644
--- a/ctypes_generation/generate.py
+++ b/ctypes_generation/generate.py
@@ -22,7 +22,7 @@ TYPE_EQUIVALENCE = [
     ('BYTE', 'c_ubyte'),
     ('PWSTR', 'LPWSTR'),
     ('PCWSTR', 'LPWSTR'),
-    ('SIZE_T', 'c_ulong'),
+    ('SIZE_T', 'c_size_t'),
     ('PSIZE_T', 'POINTER(SIZE_T)'),
     ('PVOID', 'c_void_p'),
     ('PPS_POST_PROCESS_INIT_ROUTINE', 'PVOID'),
diff --git a/windows/alpc.py b/windows/alpc.py
index 4987cd3..f090b7b 100644
--- a/windows/alpc.py
+++ b/windows/alpc.py
@@ -57,8 +57,10 @@ class MessageAttribute(gn.ALPC_MESSAGE_ATTRIBUTES):
         res = gn.DWORD()
         try:
             windows.winproxy.AlpcInitializeMessageAttribute(flags, None, 0, res)
-        except windows.generated_def.ntstatus.NtStatusException:
+        except windows.generated_def.ntstatus.NtStatusException as e:
+            # Buffer too small: osef
             return res.value
+        return res.value
 
 
 class AlpcPORT(object):
diff --git a/windows/generated_def/winstructs.py b/windows/generated_def/winstructs.py
index 1fc8114..059f5fe 100644
--- a/windows/generated_def/winstructs.py
+++ b/windows/generated_def/winstructs.py
@@ -7,7 +7,7 @@ from windef import *
 BYTE = c_ubyte
 PWSTR = LPWSTR
 PCWSTR = LPWSTR
-SIZE_T = c_ulong
+SIZE_T = c_size_t
 PSIZE_T = POINTER(SIZE_T)
 PVOID = c_void_p
 PPS_POST_PROCESS_INIT_ROUTINE = PVOID