Unable to Clone

Every few months I clone the disk in my laptop to an identical disk, I've been doing this for years and its always worked perfectly until recently, for some reason I'm now unable to clone. Both the source disk (Disk 1) and the target disk (Disk 2) are recognized and listed when I launch DD, but when highlight Disk 1 and then click to clone it, the window that pops up doesn't have Disk 2 listed so that I can select it, the list is empty. Recently I finally made the switch from XP to 7, yet I've cloned the disk since that change, so don't know for sure if this is the problem. The only other thing I can think of is that my version of DD says Update 2, I don't remember when I would have updated the version, maybe it was recently, could this be the problem?