ExecEventNotifyByMailSettings Method is not working through .Net C#

Team,

I am working .Net code which connects to Hpqc using OTA client. I am using the ExecEventNotifyByMailSettings Method to trigger the mail but mail is not getting triggered

I am setting up following information for every testest

ExecEventNotifyByMailSettingsmail = tst.ExecEventNotifyByMailSettings;

mail.EMailTo = "first.last@mail.com";

mail.UserMessage = "test";

mail.set_Enabled(0, true);

mail.Save();

but it is not working.

If i go hpqc and select testset, open automation tab and provide above information ... if i run it ... it works perfectly...

hpqc send email after complition of testset... but its not working when i am setting it from thro .NET code and executing test from .Net

Let me know, if some one has anything input on above.

Thanks & Regards,

Kamleshkumar Gujarathi