The Product Key (Product Key) entered does not match any Windows image available for installation. Type a different product key.

How To Installing Windows 8 with built-in BIOS key?

Lately it has been posted many machines that comes with Windows 8 installed, and the key (product-key) product comes contained within the BIOS, so that typing the same during setup is not required.
The problem is that if you try to install Windows 8 on a computer with the key inside the BIOS, and use a different setup with any version of the one that came on the computer, you receive the following error:

The Product Key (Product Key) entered does not match any Windows image available for installation. Type a different product key.

How to Solve 
To resolve this error, just add a file within the folder that contains the system image on the installation media. 

Simply put: just copy a file of instructions called ei.cfg in the sources folder installer.

1. Create a file with any text editor called ei.cfg;
2. Copy this code inside:
[EditionID]
Professional
[Channel]
Retail
[VL]
0
3. Move or copy this file to the Sources folder that is inside your installation of Windows 8.
Ok, problem solved. 
You no longer receive the error Incorrect key, and you can install Windows 8 normally.

If not
If the keep giving the same error, make sure the file is really a. CFG, or if it is just a file. Txt. 

To verify this, check the Folder Options in Windows Explorer, as shown in the picture below

Inside the folder options, go to the View tab, and check "Hide extensions for known file types" option is checked, as shown in the image below.

If checked, uncheck and check the ei.cfg file you created. If it is in fact a. Txt or any other, now the true extent will be displayed, and the file will be named as ei.cfg.txt, for example. 
Delete the last extension, leaving only ei.cfg, and try to install Windows 8 again.