Help! I seem to be having so much trouble with drives. I've got a problem which I've had in the past and was quite easy to sort out with a quick registry hack. However I can't remember what I did, and any search terms I'm inputting into google or MS are completely wide of the mark.

What's happening is, when I open Explorer and double click a drive in the right hand pane, I get a command prompt instead of the contents of the drive, ie D:\ in the command prompt window. I can right click and choose "explore" or I can access the drive from the left hand pane, but not the right hand side. I was hoping to take a backup of my system before going out in about 10 minutes but clearly I'm not backing up such a flakey snapshot as this.

It's the XP install, by the way, not Vista. Can anyone find anything relevant? Many thanks.