alerts in asp.net

hi

i am developing a website,which needs to generate automatic alerts,when lease period(Expiry Date)is over.
I will save Expiry date in my database,so i need to get exp date from sqlserver and i need to send automatic email before two days to expiry date.(like birthday alerts will come before two days)


iam using Asp.Net and C# for my development.

for this purpose,which topic is better to follow.

give me suggestions.

thanks
srinu ganaparthi
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