Google checkout order placing response error

Question

Hi,

I am using google checkout in my site.

But i'm not geeting response from there when i place an order.

Showing an error

"We encountered an error trying to access your server at http://www.mysite.com/cti-dev/check-out/test.php -- the error we got is Send failed with code: 401. Response body was: Failed to Get Basic Authentication Headers"

what will be the exact reason for this.

Can any one tell me how can i solve this.

Please give exact method to solve this

Thanks