I started upgrading an ASP.NET 1.1 project to 2.0, and I got this error: "Unrecognized attribute 'requirePermission' (C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Config\machine.config line 14)"

Googling revealed very little in the way of resolutions. After much fruitless tweaking, I finally removed the web project and re-added it using the filesystem directory instead of the http://localhost reference. After that, the app launched with the ASP.NET Development Server instead of IIS and the error went away. Weird.

UPDATE: Updated to fix backslashes, I hope.