The current build operation (build key Build Key[Microsoft.Practices.EnterpriseLibrary.Data.Database, Application]) failed: Unable to find the requested .Net Framework Data Provider. It may not be installed. (Strategy type Configured Object Strategy, index 2)

Unable to find the requested .Net Framework Data Provider. It may not be installed. (Strategy type ConfiguredObjectStrategy, index 2)

Then Paste the following code in Web.Config

<system.data>

    <DbProviderFactories>

      <add name="Oracle Data Provider for .NET" invariant="Oracle.DataAccess.Client" description="Oracle Data Provider for .NET" type="Oracle.DataAccess.Client.OracleClientFactory, Oracle.DataAccess, Version=2.112.3.0, Culture=neutral, PublicKeyToken=89b483f429c47342"/>

    </DbProviderFactories>

  </system.data>

This DbProviderFactories should be matched with machine.config

which you can find in the following path

C:\Windows\Microsoft.NET\Framework\v2.0.50727\CONFIG\machine.config