How to Run my .exe file or Application in the Background using .NET Application like explorer.exe file is Running always in the Background...(you can see in task Manager..)

Hi ,

This is Sundar , i want to develope one small Application in windows or web ,that should send the mail continiously according to at what time scheduled in the application and that should Running in the Background always like windows service,SQL server ........

so , please help me ......................
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