I have an SMTP server that is particularly fussy.

It is not letting me send mail, for the following reason:

[12:52:26] C: EHLO Main
[12:52:26] S: 250-mail.server.address
[12:52:26] S: 250-PIPELINING
[12:52:26] S: 250-SIZE 31457280
[12:52:26] S: 250-VRFY
[12:52:26] S: 250-ETRN
[12:52:26] S: 250 8BITMIME
[12:52:26] C: MAIL FROM:<FromAddr> SIZE=570
[12:52:26] S: 250 Ok
[12:52:26] C: RCPT TO:<toAddr>
[12:52:27] S: 504 <Main>: Helo command rejected: need fully-qualified hostname

(I have edited the above, removing mail addresses and server names)

I guess the problem is just sending "EHLO Main" - Main being the computers name.  It is part of a home network (workgroup) so doesn't have a fully qualified domain name.  But even when I tried to add one under "system properties" "computer name" "change" "more" and add a primary domain suffix, this was not sent to the mail server.  

How can I change what gets sent in the EHLO line, to make the server happy?

Alan