Do you have an OEM computer with UEFI firmware (BIOS) embedded Windows 8/8.1/10 product key?
If you have an OEM computer with UEFI firmware (BIOS) embedded Windows 8/8.1/10 product key, the Windows 10 November Update (build 10586) installer should automatically detect product key from UEFI firmware (BIOS) and you will be taken straight to the License Agreement screen.
When installing Windows 10 November Update (build 10586), the Windows installer uses the following priority logic for product keys:
1. Answer file (Unattended file, EI.cfg, or PID.txt).
2. Product key in the UEFI firmware (BIOS).
3. Product key entry screen.
If a key is supplied, the key is attempted to be use with the image that are available on the media being installed. If there is no product key supplied in the step 1 and step 2, you will get the product key prompt during setup.
If you want to choose which one will be installed (see screenshot below).
Copy the ei.cfg file to the sources folder on the USB flash drive.
Before creating the "ei.cfg" file make sure its not "ei.cfg.txt", it must be "ei.cfg".
Use a PID.txt in sources folder to automate product key entry.
Place your Windows 8/8.1/10 key in where the X's are and copy the PID.txt file to the sources folder on the USB flash drive.