I have installed exim4 on my computer and am using a dynamic dns service to handle mail forwarding and I have my router port forwarding port smtp, pop and imap to one of my computers. I get the following error in my log file:

temporarily rejected RCPT <abc@domain.org>: transport "mail_pipe" not found in local_user router

Can someone make some sense of this error. Also why is the local_user router when I sent the message to abc@domain.org. Any help is much appreciated.