Hi whenever i am trying to send the mail from my application on account creation i get the following error.

User not local; please try a different path. The server response was: Bad Recipient at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, SmtpFailedRecipientException& exception)

Smtp settings provided by client is all right.When i replace my smtp setting with gmail smtp settings on web.config mail is going smoothly.but when my smtp setting is set to the smtp setting provided by client above error occurs.

I have the folloeing in my web.config.