timmmy159 on "[Plugin: YOP Poll] An error has occured!"

I set up the website with different WordPress Address (URL) and Site Address (URL).
when I try to vote from the site address. It shows me
"An error has occured!".
Also, I vote from the WordPress Address (URL)(without login). It shows the same result.

But I vote from the WordPress Address (URL)(with login). It works fine...

What can I do to fix this error?

http://wordpress.org/extend/plugins/yop-poll/