System boots to Log In screen but Keyboard not working

I have two Hard Drives Drive A and Backup Hard Drive B [Both 3.5 Sata Drives]

My Desktop has a removable Hard Drive bay, so I can boot to either drive.

I also have a StarTech Hard Drive dock that allows me to connect either Hard Drive via USB.

My problem is that when my Backup Drive B boots, it boots to the log in screen but my keyboard will not work.

When I start Drive B in safe mode the keyboard works, for example shifting up or down to choose the safe mode options. So at the dos level the keyboard works.

Using Drive A to boot and Drive B as a USB connected Hard Drive, I can read and write to Hard Drive B.
I have run Chkdsk, Malware Bytes, AVG antivirus, and Microsoft Security Essentials on Hard Drive B. No problems found.

1. Question 1 I am thinking that some "drivers" might not be loading. I don't know much about drivers. Does this sound like a possible problem to you guys?

2. Question 2 Where are my drivers located on Hard Drive A?

3. Question 3 Can I copy the drivers on Hard Drive A to Hard Drive B?

Thanks Ramhound

With only Backup Drive B on the computer, boot from win 7 installation disk.
Go to repair and launch a cmd window.
Type and run: sfc /scannow

Drivers are on C:\Windows\System32\drivers. But if they aren't called to load, to have them won't help.

Did you booted on Safe Mode. Did it stopped and took long to load a particular driver?