I was having the same problem as everyone else here. CommandCenter4 would not open. My fix was simple. I had to remove the "Dell" folder from the C:/windows/twain_32 folder. That is all it took. I didn't delete the folder, I just moved to my desktop to see if that fixed it and it did. I guess my old Dell printer installed that folder a while back and it was interfering some how. Every thing seems to be working just fine now.
The Dell thing worked for me too on this problem. Which is weird because we have no Dell hardware in our office. Its all Brother printer, Canon printer, HP printer, and my computer is an HP. I don't know why it made a Dell folder.