I think I am using Rox, but I have added items to Startup before so I can do that again now.Are you using pcmanfm or thunar as your file manager? If so, select /usr/local/bin/desktop_drive_icons, to to menu edit-create link, and put a link in /root/startup. That should start it up automatically every time.]
I will give it a whirl and see if that sorts it out. At least now I know the name of the program I can run if they disappear again in another lifetime (instance of Debiandog) !!
Thanks for all your help.