i have a asp.net web application written about 2 years ago .It does not have any logging mechanism in it. Ideally I would like to log any errors that happen especially at the database level. I cannot afford to break the application however, and I have limited time.

I have heard about **ELMAH**. Is it possible to have something that doesn't talk to my code directly and just does its own thing by monitoring the server?

* It was made in ASP.NET 3.5.
* It has AJAX as well as heavy use of ViewState.
* The application also communicates with Excel.
* It is built in Visual Studio 2008 w/ SQL Server 2005 on the backend.

How do I go about deploying this website with above requirements?