I was working with a WordPress plugin and I needed to import a load of products, no problem there is a CSV import option.
I tediously went through the products and entered them into a file, saved as CSV and uploaded. Unfortunately, the file was not recognised as nothing was imported.
I tried entering the encoding UTF-8 option but still no joy.
Eventually, I found that saving the file as a MS DOS csv file in Excel and then uploading worked fine.
I use Excel 365 but it should be the same for the previous versions.