先上Log：
2014-01-11 14:51:19 Running command: "['D:\\development\\Python27\\pythonw.exe', 'D:\\development\\Google\\google_appengine\\dev_appserver.py', '--skip_sdk_update_check=yes', '--port=10080', '--admin_port=8002', u'D:\\development\\Google\\google_appengine\\projects\\helloworld']"
Traceback (most recent call last):
File "D:\development\Google\google_appengine\dev_appserver.py", line 197, in <module>
_run_file(__file__, globals())
File "D:\development\Google\google_appengine\dev_appserver.py", line 193, in _run_file
execfile(script_path, globals_)
File "D:\development\Google\google_appengine\google\appengine\tools\devappserver2\devappserver2.py", line 32, in <module>
from google.appengine.tools.devappserver2.admin import admin_server
File "D:\development\Google\google_appengine\google\appengine\tools\devappserver2\admin\admin_server.py", line 29, in <module>
from google.appengine.tools.devappserver2.admin import console
File "D:\development\Google\google_appengine\google\appengine\tools\devappserver2\admin\console.py", line 22, in <module>
from google.appengine.tools.devappserver2 import module
File "D:\development\Google\google_appengine\google\appengine\tools\devappserver2\module.py", line 69, in <module>
from google.appengine.tools.devappserver2 import wsgi_server
File "D:\development\Google\google_appengine\google\appengine\tools\devappserver2\wsgi_server.py", line 31, in <module>
from cherrypy import wsgiserver
File "D:\development\Google\google_appengine\lib\cherrypy\cherrypy\__init__.py", line 70, in <module>
from cherrypy import _cptools
File "D:\development\Google\google_appengine\lib\cherrypy\cherrypy\_cptools.py", line 245, in <module>
from cherrypy.lib import cptools, encoding, auth, static, jsontools
File "D:\development\Google\google_appengine\lib\cherrypy\cherrypy\lib\static.py", line 7, in <module>
mimetypes.init()
File "D:\development\Python27\lib\mimetypes.py", line 358, in init
db.read_windows_registry()
File "D:\development\Python27\lib\mimetypes.py", line 258, in read_windows_registry
for subkeyname in enum_types(hkcr):
File "D:\development\Python27\lib\mimetypes.py", line 249, in enum_types
ctype = ctype.encode(default_encoding) # omit in 3.x!
UnicodeDecodeError: 'ascii' codec can't decode byte 0xb0 in position 1: ordinal not in range(128)
2014-01-11 14:51:21 (Process exited with code 1)
解决方法：
到Python的安装目录$python$下，在$python$/lib/mimetypes.py中，找到
try:
ctype = ctype.encode(default_encoding) # omit in 3.x!
except UnicodeEncodeError:
pass
将其注释