Asp.net Runtime Error Unrecognized Configuration Section Authentication

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Unrecognized Element Authorization

policies of this site About Us Learn more about Stack Overflow the company Business Learn unrecognized configuration section pages more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow unrecognized configuration section configuration Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Unrecognized configuration section system.web/configuration up vote 1 down vote favorite 1 i'm getting this "Unrecognized configuration section system.web/configuration when i set my admin,staff and user authentication .please help me with this.by here i provide the web.config code http://stackoverflow.com/questions/8112977/unrecognized-configuration-section-system-web-configuration Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Unrecognized configuration section system.web.extensions up vote 0 down vote favorite I am trying to run a project on my http://stackoverflow.com/questions/17403270/unrecognized-configuration-section-system-web-extensions machine, but get the error Unrecognized configuration section system.web.extensions. Could someone please tell me what the problem is? I thought it could of been that i did not have the correct .Net version, but i just downloaded and repaired the .Net 4.5 on my machine. My Web.config looks as follows: