problem in sending bulk emails.

Hello,


 I have a requirement of sending 3000 Emails one by one with an attachment of around 100KB,
I was using System.net.mail namespace with our company mail server.
my program will send upto 360 mails after that it is not sending emails,and it is not giving any exception.
what is the solution to my problem.


Please any one send solution to my problem  asap.


Thanks in Advance.


Regards,
prasanth.

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