GTranslate pro gives me a blank page

[cliang]

My website is:
http://chinesecef.org/

and
http://chinesecef.org/en/
gives me errors:

Not Found
The requested URL /en/ was not found on this server.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

My default language is Chinese: ZH-CN

Any ideas?

[Edvard]

Did you read this before posting? gtranslate/troubleshooting-gtranslate-pro-t368.html