Opening CSV files in Excel 2016

I have a new install of Excel 2016, that hates CSV files. It opens them with everything in one column flagpole style, down column A, with commas and speech marks visible.

Salient points:

1. I have two machines, desktop and laptop, both running same version of Excel. Desktop works fine, opens the same problem files formatted correctly.

2. I can create CSV files on laptop, save those, open them again on laptop, and it's fine.

3. Even opening it in Notepad++, saving in the hope of some sort of file format normalisation, and still no good.

4. I have compared regional settings and almost all settings in Excel.

5. I tried renaming the file to TXT, it brought up the text file conversion dialogue, I chose comma delimited. First time it ignored that, still got everything in column A, second attempt, that actually worked, however, that is a pants solution, I want to be able to just natively open CSV files without saving as TXT, I use many different ones every day.

Anyone got any ideas?

Thanks in advance.