My secondary Drive was "D:" and I just replaced it today and when I put the new hard drive in it was Drive "K:". Drive "D:" is now a "CD Drive" in My Computer. I went to Manage, Disk Management but I am unable to select "D:" because it was taken. But I was also unable to find the "CD Drive" to try to change it. I have 2 DVD+RWs, 1 Virtual DVD, and a Internal Memory Card Reader. I'm not sure where the CD Drive came from and how it defaulted to my D: drive letter. Heres a screen shot.
I do not know why you cannot select the CD drive. You could try this: unplug everything but the hard drives. Assign them the desired drive numbers. Then add the rest gradually. The "off- reboot" sequence will take patience, but it should work for you.
I had a similar problem once, and that's how I fixed it.
You do this as a two-stage process of renaming. First stage creates a space, and second stage names them all properly.
First, you must identify what is what now. You know the C: and K: drives for sure. You need to know which DVD unit is E:, F: and L: (one may be your virtual drive). And which thing is the card reader? With that you can build a list of what you want them to be after the second stage is complete. Suppose it is to finish as:
C: is boot drive
D: is second HDD
E: is top DVD-RW
F: is bottom DVD-RW
G: is card reader
H: is virtual DVD
Now, I:, J: and K: are already in use, so start renaming things after that.
Leave the new second HDD as K:
Rename the top DVD-RW to L:
Rename the bottom DVD-RW to M:
Rename the card reader to N:
Rename the virtual DVD to O:
If anything still is using a letter from D: to H:, rename it, too. That's stage 1. Reboot to establish this interim naming system.
Now start back through, renaming each device to what you want it to be. All those names should be available. When you're done, reboot and come back to Disk Manager. Check that they all look right, and check in My Computer that they all have the right stuff on them and the names are what you intended. Now, in Disk Manager, are there any named devices that don't actually exist? You might need to delete those devices and reboot to clean up.
By the way, how is the Virtual DVD established and named? Is that by a driver automatically loaded as Windows boots? Maybe it would be easier to delete that drive right from the start and reboot without it. Then when you 're all done, re-create that Virtual DVD and it will come in as the new last device.