title: Sections must only appear once per config file. See the help topic <location> for exceptions.Why?
body: <blockquote>
    <p>Configuration Error
    Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately. </p>
  </blockquote>
  
  <pre><code>&lt;configuration&gt;
  
    &lt;system.net&gt;
      &lt;mailSettings&gt;
        &lt;smtp from="makovetskiyd@yahoo.co.uk"&gt;
          &lt;network host="smtp.gmail.com" enableSsl="true" defaultCredentials="false" port="587" userName="****" password="****"/&gt;
        &lt;/smtp&gt;
      &lt;/mailSettings&gt;
    &lt;/system.net&gt;
  
    &lt;connectionStrings&gt;
      &lt;clear/&gt;
  &lt;add name="SqlState" connectionString="Data Source=localhost;DataBase=AnyNameOfServerState;Integrated Security=True" providerName="System.Data.SqlClient"/&gt;
  &lt;add name="YourGuruDB" connectionString="Data Source=DIMA-00AA1DA557;Initial Catalog=model;Integrated Security=True"/&gt;
  &lt;add name="modelConnectionString" connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename='D:\Documents and Settings\Dima\My Documents\Visual Studio 2010\WebSites\WebSite10\App_Data\ASPNETDB.MDF';Integrated Security=True;User Instance=True;Trusted_Connection=Yes;" providerName="System.Data.SqlClient"/&gt;
    &lt;/connectionStrings&gt;
  
  
    &lt;system.web&gt;
  
  &lt;sessionState mode="SQLServer" sqlConnectionString="SqlState" allowCustomSqlDatabase="true" cookieless="false" timeout="20"/&gt;
  &lt;compilation debug="true"/&gt;
  
  &lt;authentication mode="Forms"&gt;
    &lt;forms name=".MyCookie" loginUrl="~/Registration.aspx" protection="All" timeout="30" path="/"&gt;
      &lt;credentials passwordFormat="MD5"&gt;
        &lt;user name="****" password="****"/&gt;
      &lt;/credentials&gt;
    &lt;/forms&gt;
  &lt;/authentication&gt;
  
  &lt;authorization&gt;
    &lt;deny users="?"/&gt;
    &lt;allow users="*"/&gt;
  &lt;/authorization&gt;
  
  &lt;roleManager enabled="true" defaultProvider="MyRoleProvider"&gt;
    &lt;providers&gt;
      &lt;clear/&gt;
      &lt;add name="MyRoleProvider" applicationName="/" connectionStringName="modelConnectionString" type="System.Web.Security.SqlRoleProvider"/&gt;
    &lt;/providers&gt;
  &lt;/roleManager&gt;
  
  &lt;membership defaultProvider="MyMembershipProvider"&gt;
    &lt;providers&gt;
      &lt;clear/&gt;
      &lt;add name="MyMembershipProvider" type="System.Web.Security.SqlMembershipProvider" connectionStringName="modelConnectionString" minRequiredPasswordLength="1" minRequiredNonalphanumericCharacters="0" enablePasswordReset="true" maxInvalidPasswordAttempts="1000" passwordAttemptWindow="4000" enablePasswordRetrieval="true" requiresUniqueEmail="false" passwordFormat="Encrypted" applicationName="/WebSite10"/&gt;
    &lt;/providers&gt;
  &lt;/membership&gt;
  
  &lt;machineKey validationKey="****" decryptionKey="****" validation="SHA1" decryption="AES"/&gt;
  &lt;compilation debug="true" targetFramework="4.0"&gt;
    &lt;assemblies&gt;
      &lt;add assembly="System.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=****"/&gt;
      &lt;add assembly="System.Web.Extensions.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=****"/&gt;
      &lt;add assembly="System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=****"/&gt;
      &lt;add assembly="System.Data.Linq, Version=4.0.0.0, Culture=neutral, PublicKeyToken=****"/&gt;
    &lt;/assemblies&gt;
  &lt;/compilation&gt;
  </code></pre>
  
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