First thing I learned was not to try to back up the whole of your hard drive at one go!
When I got back to the computer roughly twenty-four hours after starting the first 'save' only 19% had transferred.
I think this was partly because I had not set the programme so that it would go on saving when the computer logged me out automatically after a few minutes of keyboard inactivity.
With help from the company providing the trial, I set that right. And I chose more carefully the files to save.
That amounted to slightly more than 2Gb. I did not save pictures and music.
I'll try to build up the amount of material backed up over the next few days.
It would be a pity, after all, to have to reload all your music in a world where more and more of what we listen to, and watch, is stored on hard drives.
Online TiVo backup, anyone?