my application is developed on classic asp, but also uses asp.net as I am migrating the application on .Net. Its using SQL server as database and hosted on Windows server 2003.<
It sounds a lot like there's an unmanaged resource of some kind that you aren't cleaning up properly. We don't have enough information to know exactly what that resource might be, so all we can do is guess.
My first instinct is database connections, except that restarting that restarting sql server should fix it if that were the case. Next on the list is file handles and threads, so if you do any multithreading work or extra file io that would be something to look at. Remember, in ASP.Net, the using
statement (not directive) is your friend.