If you are asked to enter a product key during the installation process, use this generic key.
This is the generic key for W8.1 'Standard.'
When you get to the screen that asks 'Where do you want to install Windows,' delete every partition on the hard drive, leaving just one partition of unallocated space. Click Next, and W8.1 should begin to install.
If you had to enter the generic key, manually change the generic product key to the W8 key in your PC's BIOS in the PC settings menu.
After you get W8.1 installed, and you had to manually enter the W8.1 generic product key, you will need to run the free utility I zipped up and attached below, that will show you show the W8 product key in your PC's BIOS.
I have also zipped up and attached below, the Microsoft tool which hopefully will transfer the ISO file to a DVD or USB flash drive so it is bootable. Or you can use a free utility such as Rufus.
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