I have received two data files, a spreadsheet file in .xlsx format and a .csv file. These are bundled in a winmail.dat file.
I can open it when in my linux system with KTnef, no problem, but I wish to save the .csv file on its own in one of my working files as just that, a csv file.
Try as I might I cannot do this as everything I try insists on opening it in a spreadsheet.
If you really need a csv file, you might go through with the loading into spreadsheet “libreoffice calc” as you say is suggested by the app and then save back to a csv file.
From what i can see in KTnef, you should be able to save individual files. When you open the winmail.dat file in KTnef, is the extract button not active?