title: Script to convert .csv file to .xlsx
body: <p>I want to convert .csv files to .xls. The files are created by another application without .csv suffix (<code>ex.1</code> for example). I have background in C++ and C#.
  There are a lot of VBScript examples but I don't know how to start, where to write the script, how to run it. I would appreciate a detailed answer.</p>