This exception probably happen because of new unsaved view, which view.file_name() return None:
Traceback (most recent call last):
File ".\sublime_plugin.py", line 175, in on_load
File ".\sublime_plugin.py", line 154, in run_timed_function
File ".\sublime_plugin.py", line 174, in <lambda>
File ".\sublime_rope.py", line 436, in on_load
self._check(view)
File ".\sublime_rope.py", line 478, in _check
view.file_name().encode('utf-8')
AttributeError: 'NoneType' object has no attribute 'encode'
This exception probably happen because of new unsaved view, which view.file_name() return None: