Actually importing gene names was possible without having autoconverted names, you had to make sure you were importing files using an import tool, currently listed under the "Data" tab and then importing data from file/web or data, or use the button specific for .csv/txt. In this way, Excel would open gene data in a table editor without renaming gene names if you made sure, this has been possible since at least 2005 I believe, or maybe even earlier. It was critical to not just auto-click or open a .csv or .txt file with Excel, but specifically open a blank or existing workbook and then use the import tool from inside the application. Opening data table files directly with Excel was/is typically bad practice.