Yeah I know its years too late but anyone that has failed to connect a dimage 7i and other models over USB to windows 7 or later...
So you have done everything right and the windows computer won't give you the 'bong' when you plug in the Minolta USB cable. No new drive appears.
Well I stumbled on the solution while trying to fix something else!
The camera needs to set up the CF card to look like a disk drive to its USB port and it can't do it if its is bigger than 1 GB. So it just gives up and never connect to the PC. No error messages. Solution is, if the card is bigger than 1GB, partition it on a PC so it looks 1Gb. Now it will connect
The problem I was originally seeking was that my card was FAT32 and the camera needs FAT. I am using a CF to micro SD adapter with a 32Gb card. I needed to repartition it to be below 4Gb so that I could format it as FAT. I looked in the camera manual and saw the max was 1Gb but I know that 2GB was acceptable to the camera with my previous SD card. Anyway long story short I made it 1GB and not only did it work but the USB now connects!.