Error occured, info=Failure sending mail.

 Hi,
I am trying to implement the asychronous email code demonstrated at - http://www.asp.net/learn/videos/video-420.aspx
I have copied and pasted the code to my own site so there should be no syntax errors and have spoken to my web provider about SMTP email access which they say is allowed and they advised me to use the following:
Host = localhost
Port = 25
and that SSL should not be checked - I do not have SSL set up yet anyway.
When I try to send an email I get the following message - Error occured, info=Failure sending mail.
Has anyone ever encountered this before and know how to solve it?
Thanks
Andy
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