ASP.Net MVC4 configuration error after installing MySQL Connector .NET

This solution worked for me:

<siteMap>
      <providers>
        <remove name="MySqlSiteMapProvider"/>
      </providers>
    </siteMap>

I think they forgot to put the file MySql.Web in de GAC (Global Assembly Cache)

This nasty error occurs when you install MySQL .NET Connector 6.9.4 (probably other versions too) because if you do not uncheck "Web Providers" during the installation it writes in your machine.config which brings you to this error. Be sure to read the entire answer before applying any of these steps in order to start from where you have to start.

The real problem with other suggestions is that if you are not using MySQL in every project to just add a reference to MySQL dll to mitigate the problem in every project is not an option. Every project of yours that uses ASP.NET will require it because of the rows added in machine config by the installer!

To solve the problem properly :

1. Start the installer and click "Change"
2. then remove the "Web Providers" section entirely.
3. This will remove the declarations from your machine.config (which I find a horrible thing to do in installer but the installer creates them without any notification anyway).
4. After that it is a good idea to check you machine config which you can find here. And be sure that it did not spoil both 32 and 64 machine configs.
5. When your machine config is clear add the MySql.Web assembly to your project and add the MySQLMembershipProvider declaration in your project web.config - the standard procedure.
6. Enjoy the clean installation of MySQL connector.

But if you do it that way you may try to add Ado NET Entity Data model after, right? If that is the case it is most likely that you do not see the option for MySQL as an available data source in the wizard. This is because from version 6.7 when you install MySQL Connector .NET it will no longer register as DDEX provider automatically.

To correct this issue you have to download a separate installer provided especially for MySQL and .NET from here or the just Visual Studio integration plug-in directly from here.

Be sure to check the Visual Studio integration and connector during the installation wizard on either of the above installers.

-Open the MySQL installer
-Click the remove tab to your right.
-Check all the things that are related to .Net (like connectors)
-Click remove button
-Close and reopen visual studio
-Upvote Ognyan Dimitrov's answer