Custom error settings

  Hi
I get the following error when i access my ASP.NET 2.0 application. I changed the Custom Error mode to Off. But still it shows the same error.
Why does this occur ? How to solve this?
Server Error in '/' Application. Runtime Error Description: An application error occurred on the server. The current custom error settings for this application prevent the details of the application error from being viewed remotely (for security reasons). It could, however, be viewed by browsers running on the local server machine.

Details: To enable the details of this specific error message to be viewable on remote machines, please create a <customErrors> tag within a "web.config" configuration file located in the root directory of the current web application. This < ...