Downgrading from Windows 10 to 8/8.1

[WyattWhiteEagle]

The system:
Acer Aspire V5-122P-42154G50nss
Part Number: NX.M8WAA.00732022D21200
SNID: 32014262520

Came with windows 8 preinstalled.
It has no optical drive.
The Windows 8/8.1 recovery partition has been deleted.
The usb ports work and I can get to a command prompt as well as diskpart.

After Windows 10 updates, the system begins to seem unstable
and finally boots into startup repair and recovery.

I've made all the changes in the bios and the bootable flashdrive isn't
detected by the system as being bootable.
I created the bootable on a Windows 10 system.

I also have a windows 8.1 installation disk with a good product key.

Reinstalled windows 10 without updating.
Allows access to files on the usb device.
Right-clicked "setup.exe" and chose "Run as admin".
Everything goes well until I accept Microsoft's "stuff"...LOL

Immediately after accepting, I get the following:

"Windows 8.1 Setup: Something happened, setup has failed to
determine supported install choices."

How do I get windows 8 or 8.1 on this machine?

 

[mrjimphelps]

I suggest that you purchase the Acer eRecovery Media for your computer. If you use the eRecovery Media, you can restore your computer back to original factory condition, which means Windows 8.1 (or 8.0?) with all drivers installed.

Here's where you can get it from:
eRecovery Media | Acer

Doing this will wipe your drive clean as part of the recovery process, so be sure to copy anything you want from the drive before doing this.

In the mean time, if you would rather just install Windows 8.1 from your install disk, boot the computer with the Windows install disk in the drive. At the beginning of the install process, you should be asked if you want to do a custom install; tell it that you want to do that. You will then be given the option of deleting and recreating whatever partitions are on your hard drive. You should delete all current partitions, and then create one new partition for the entire hard drive. Doing this will totally wipe your drive clean and will eliminate the problems you are currently having installing Windows 8.1.

Whether or not you plan to use the eRecovery media at this time, I highly recommend that you purchase it, so that you will have it for future use. And make a few copies of it when you receive it, because Acer will provide you only one copy.