I first encountered this error when I was building a small media player using WPF 4.0 and the embeddable open source database MySql. I added a link to the MySql.Data.MySqlClient library which was built on a lower version of the .Net framework than the one which the current application is running on. The screen is as shown below




In order to correct the error, an app.config file must be added to the project and then the following code is copied into the configuration file.


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