I am currently working on a VS 2003 solution using VB.NET. Each time one of the team members loaded the web project our exception handling block would log a weird exception: the page requested get_aspx_ver.aspx. The exception tried to load our default error page and emailed us the proper notification.
Weird… we are not executing any code when loading the project… wrong, this mysterious page is called…
Visual Studio .NET 2003 makes an http request to the non existent web page: http://yourserver/yourweb/get_aspx_ver.aspx in order to determine the ASP.NET version installed on your web server (this information is returned in the http headers for the request). Since the page does not exist on your web server, your error handler is called.
One possible work around is to have your error handler ignore failures to this page, which is exactly what we did.
Related problems are described here:
and on this post in aspnetresources.com.