An error occurred creating the configuration section handler for system.data: Column 'InvariantName'

Hi, insandur 

You can locate the machine.config file:
For 32-bit systems: C:\Windows\Microsoft.NET\Framework\v4.0.30319\Config\machine.config
For 64-bit systems: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Config\machine.config
Then open the machine.config file in a text editor with administrative privileges. Search for the MySql.Data.MySqlClient entry under the <DbProviderFactories> section. Try to Remove or comment out the duplicate entry. Ensure that only one entry for MySql.Data.MySqlClient exists. Save the file and restart your application or service.

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Best Regards

Yongkang Hua

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