Setting up SMPT server

I tried setting up the SMTP boxes in Global Options, in order to e-mail the results, but got the message below.
In the e-mail address box I filled in my normal full e-mail address and in the outgoing server name I filled in 'mail.btinternet.com'
Can you advise what I may have done wrong??

Version: 2.00 build 3
Installed: Unknown
Time: 12:43:42
There was a problem sending your email; details appear below.

2009.04.22 12:42:40 (Wed)------------Start of Session-----------------
Blat v2.5.0 w/GSS encryption (build : Sep 14 2005 22:46:29)
Sending C:\DOCUME~1\David\LOCALS~1\Temp\blw4D.htm to results@belfastloughsailing.org
Login name is david.mcmullan@btinternet.com
Attached text file: C:\DOCUME~1\David\LOCALS~1\Temp\blw4B.htm
The SMTP server does not like the sender name.
Have you set your mail address correctly?
Error: Connection to server was dropped.
2009.04.22 12:42:42 (Wed)-------------End of Session------------------

C:\PROGRA~1\Sailwave\blat.exe "C:\DOCUME~1\David\LOCALS~1\Temp\blw4D.htm" -to "results@belfastloughsailing.org" -subject "BYC Regatta data" -f "david.mcmullan@btinternet.com" -server "mail.btinternet.com" -port "25" -log "C:\DOCUME~1\David\LOCALS~1\Temp\blw4C.htm" -attacht "C:\DOCUME~1\David\LOCALS~1\Temp\blw4B.htm"

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Date: 22 April 2009
Subject: BYC Regatta data

Try v2.01 build 1 on the website.

CJ

david78882 wrote:

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results@belfastloughsailing.orgdavid.mcmullan@btinternet.com"results@belfastloughsailing.org""david.mcmullan@btinternet.com"http://www.yachtsandyachting.com/http://www.sailing.org/http://www.sailwave.com/http://www.abyc.org/upload/Sailwave_ABYC_User_Guide.pdfsailwave-digest@yahoogroups.comsailwave-unsubscribe@yahoogroups.comhttp://groups.yahoo.com/group/sailwave/http://groups.yahoo.com/group/sailwave/joinmailto:sailwave-digest@yahoogroups.commailto:sailwave-fullfeatured@yahoogroups.comsailwave-unsubscribe@yahoogroups.comhttp://docs.yahoo.com/info/terms/www.avg.com