The problem: You’re trying to use the Table Data Import Wizard in MySQL Workbench to import a CSV file into a database and it’s giving you the following error:
This file type is not supported, valid options are CSV, JSON
However, you are sure that the file is a CSV file.
The solution that worked for me (with MySQL Workbench 8.0): Renaming the CSV file from DATA.CSV to DATA.csv. Yes, MySQL Worbench did not like the capitalization of the file extension.