error message in returned e mail:-452 message rejected (in reply to
end of DATA command)
Can someone explain this to me. Have contacted my ISP (wanadoo.fr) and
the ISP of person to whom I sent the e mail(tesco.net) and have had no
reply from either. I know that the address is correct because in every
case I hit the reply button. I use Outlook.

The SMTP (simple mail transfer protocol)
    http://www.ietf.org/rfc/rfc2821.txt
describes code 452 as
 452 Requested action not taken: insufficient system storage
so probably some host involved in the transmission of your mail has a
full spool directory.

The 4xx messages are temporary failures unlike 5xx messages which are
permanent and might be the result if the mailbox of your recipient was
full.

In fact the RFC says more about 452 - perhaps the number of recipients
is over 100 and that can cause it.

And the term "temporary" is from the point ov view of the mail s/w. 
That transmission has probably failed permanantly unless there's
something in the
status notification that says otherwise.

I think the Error is because of the Storage Capacity being Full.
The person may be having an option of Leave message on Server .. and
may be that the Storage capacity has exceeded on the server. plz chk
out abt that.. and your issue will be solved.
Thank you

KrisssstheSolver :)

Thanks to bozo99 and Krissssthe solver for your help. Will check it out!