global.asax Application_Error not firing

My global.asax seems not to be firing. I have:

void Application_Error(object sender, EventArgs e) 
{ 
    // Code that runs when an unhandled error occurs
    Server.Transfer("~/ExceptionFormView.aspx");
}

In my web.config, I don't have anything like CustomErrors. As I want everything to be handled by Global.asax and transferred to ExceptionFormView.aspx.

It works fine locally, but not when we deploy to servers. Any thoughts?

Do I need PrecompiledApp.config?