This message was posted on behalf of Intel Corporation
Thank you for contacting the Intel® Communities Team. I understand you are facing some problems installing Windows 7* on your NUC. Allow me to help you regarding this issue you are having.
The “Legacy Boot” should not be a problem to complete this installation nonetheless, you can always set your BIOS settings back to default by accessing the BIOS interface pressing F2 during the NUC boot and F( to restore the setting to default.
The steps you need to take into consideration in order to properly install the Operating System are the following:
- Make sure to create the bootable image on a computer with Windows 8.1* Pro installed.
- The image and the USB 3.0 drivers should be installed as well on the machine with Windows 8.1* Pro. The tool in order to install the 3.0 drivers can be downloaded by clicking here.
- The USB drive must be 3.0 as well as the USB port is connected when the image is created on it.
- You can complete the installation using the following guide: https://www.intel.com/content/www/us/en/support/articles/000017241/mini-pcs.html
I hope this help you in order to complete the installation of your Operating System,