Error Unable to find the requested .Net Framework Data Provider. It may not be installed. (4 replies)

Hi all.
I'm install MySql Connector 6.7.4 over NuGet. I'm create connection string in App.Config:
<connectionStrings>
<add name="TodoContext" connectionString="server=localhost;uid=todo;database=todo;Pwd=xxxxxx;" providerName="MySql.Data.MySqlClient" />
</connectionStrings>
After run i'm get error: Unable to find the requested .Net Framework Data Provider. It may not be installed.
In this code:
var db = new TodoContext();
db.Todoes.Add(new Todo()
{
Text = "Test task #" + new Random().Next(),
DueDate = DateTime.Now,
Priority = new Random().Next(),
CreateTime = DateTime.Now,
Description = "bla bla bla"
});
Error fire on Add line. Please help me resolve it problem.