When running the System Configuration Wizard The following error may appear in certain cases shortly after launch and before any user interface is presented.
The invocation of the constructor on type 'ServerConfigurationWizard.UserControls.SQLServerSelector' that matches the specified binding constraints threw an exception.
The resolution for this error can vary depending on the specific cause. If this error appears first check the ConfigurationWizard.log file which is typically located in C:\Logs folder. If the first error in that log file appears as follows the resolution detailed in this article applies.
2015-10-15 12:52:50,900  ERROR ConfigurationErrorsException
System.Configuration.ConfigurationErrorsException: The 'DbProviderFactories' section can only appear once per config file.
This can be resolved by making a change to the machine.config file. On a sample Windows Server 2012 setup this file is located in this folder:
This file will have multiple entries for DbProviderFactories. Determine which entry is necessary per the client environment and remove the duplicate entry. An iisreset and/or a full reboot of the server after making this edit may be required.
The file may look something like the following (duplicate line to remove is highlighted red with strike-through):