Windows 8.1 installation killed working Windows 7 install

I need some assistance.
Previously I had Windows 7 64 installed on Hard Disk. I decided to re-install on a SSD drive without wiping the hard drive and everything went as planned. When I boot it gives me a text screen boot choice of Windows 7 SSD or Windows 7 HDD......So I thought I knew what I was doing.

Needed Windows 8.1 for some Bluetooth work so I installed a second Samsung SSD and proceeded to install Windows 8.1. Upon completion of the install Windows 8.1 boots up and Shows a Nice icon screen of OS choices Windows 7 SSD, Windows 7 HDD or Windows 8.1. So for 1 minute I was impressed with Windows 8.
Until I actually tried booting Windows 7!
On restart I got an error....
a Recent hardware/software change installed a file that is signed incorrectly.
\windows\system32\winload.exe
STATUS: 0xC0000428
info: digital signature could not be verified.

I tried using the Windows 7 CD to do a repair but no luck
I tried reading some posts here and tried to follow some suggestions on this one
Windows 7 Help Forums > Windows 7 help and support > Installation & Setup » GPT Win 8 Dual boot installation killed Win 7 MBR boot option.

I installed EasyBCD and removed the Windows 7 entries and added them again but the result is still the same.
I disabled Fast startup Mode in Windows 8.1 but that didn't help
I TRIED TO DISCONNECT THE WINDOWS 8.1 DRIVE but still Windows 7 would not boot.
So now I cannot run Windows 7 drives at all.

Any help would be much appreciated.
I have an ASUS P8Z77-V MB

Can you download free Partition Wizard CD, rightclick to burn with Windows Image burner to CD, boot and post back a camera snap of the full drive map showing all listings?
Screenshots and Files - Upload and Post in Seven Forums - Windows 7 Forums
How to Boot A Computer from CD or DVD - YouTube

This sounds difficult but is really easy and will save a lot of time since we'll immediately be able to see which partition is booting the multi-boot, most likely the first installed OS, signified by the System flag. It also needs to be marked Active or else Mark Partition Active.

Then I would unplug Win8 hard drive, make sure Win7 System HD remains set first to boot in BIOS setup, boot Win7 DVD to run Startup Repair - Run 3 Separate Times to restart the Win7 Dual Boot.

If this fails, unplug the other Win7 drive and run the 3 repairs on the Win7 System partition HD until it starts.

You can then mark Active and do these repairs on the other Win7 drive while it is plugged in alone to make it independently bootable via the BIOS, or plug it in to add it using EasyBCD from the System partition HD.

Afterwards plug back in the Win8 drive making sure the System partition HD remains set first to boot in BIOS. Install EasyBCD to the System partition Win7 to add Win8. Again you could also plug it in alone, mark Active to run Windows 8 Automatic Repair from the Windows 8 disk if you want to make it independently bootable via the BIOS.

It's always best to install these OS's with all other HD's unplugged so that they are independently bootable via the BIOS boot order or Boot Menu key. If you can still add or subtract them from a Windows Boot Menu using EasyBCD but they will remain independently bootable as well so any can come and go as you please.