I have an operational exchange server that has operated fine until now. I can send emails from another address to it and recieve them. I can send internal emails fine, however when i try to send a new mail to an external address it just doesnt send, i dont get an error message it just never turns up at the recipients address and does not bounce back, i have a feeling it might be to do with the smtp server, and have also tried setting it to my isp's smtp address but neither work, any idea?