I am running into an issue I had before; can't find my reference on how to solve it.

Here is the issue. We encrypt the connection strings section in the app.config for our client application using code below:

        config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)
        If config.ConnectionStrings.SectionInformation.IsProtected = False Then
            config.ConnectionStrings.SectionInformation.ProtectSection(Nothing)

            ' We must save the changes to the configuration file.'
            config.Save(ConfigurationSaveMode.Modified, True)
        End If

The issue is we had a salesperson leave. The old laptop is going to a new salesperson and under the new user's login, when it tries to to do this we get an error. The error is:

Unhandled Exception: System.Configuration.ConfigurationErrorsException: 
An error occurred executing the configuration section handler for connectionStrings. ---> System.Configuration.ConfigurationErrorsException: Failed to encrypt the section 'connectionStrings' using provider 'RsaProtectedConfigurationProvider'. 
Error message from the provider: Object already exists.
---> System.Security.Cryptography.CryptographicException: Object already exists