Exception handling in .NET
The better approach for exception management strategy in enterprise wide ASP.NET applications is:
a) Define a set of application-specific exception types.
b) Build a logging mechanism (Event log or activity logging in DB).
c) Trap the custom Application Exceptions in an HttpModule, log them and redirect the user to a custom error page that indicates some problem has occured.
Check out this MSDN Magazine article on Exception-handling techniques
for more understanding.