无法通过联系表格7发送邮件

I am using contact form 7 for my new website. But I am unable to send the mail through contact form 7. When I press the send button, I keep on getting the message: "Failed to send your message. Please try later or contact the administrator by another method". But When I see in the contact form db, I can see the data that I have entered in The form.I am using contact form 7 for my new website. B