I have also found that by holding F2 down while powering up will go into boot options.
If Computer Boots, Recovery Click the bottom-left icon on the Start screen,
Changing the Boot Priority
Now, the boot priority has been changed so that the device
Running windows 8.1
The disk can be read under windows 7 computer. It has 6 partitions
What is CSM option in BIOS?
The disk was backed up to NAS1 with Windows 7 computer with the laptop disk connected as SATA2. When restoring to new drive, the windows 7 partition was installed and even formatting to factory original would not boot. The new drive could not be read by Windows 7.
After cleaning the laptop disk on the windows 7 computer, first time it would boot, second time it would not.
ADVANCED FORMAT drive
The new 1TB WD10JPVX is and ADVANCED FORMAT drive.
Windows 7 can convert the drive to a GPT disk
The drive was offline because of a signature conflict. Set the drive online, converted to GPT and formatted.
Master Boot Record (MBR) disks use the standard BIOS partition table. GUID Partition Table (GPT) disks use Unified Extensible Firmware Interface (UEFI). One advantage of GPT disks is that you can have more than four partitions on each disk. GPT is also required for disks larger than two terabytes (TB).Oct 12, 2017
Disable Windows 7 Update
Slowed down again by another windows 7 update
Click Start > Control Panel > System and Security > Turn automatic updating on or off. In the Important updates menu, select Never check for updates. Deselect Give me recommended updates the same way I receive important updates. Deselect Allow all users to install updates on this computer and click OK.
Now when booting the Windows 8 usb, computer says it (windows 8) can only be installed on GPT drives. So convert to GPT using the windows 7 system and now windows 8 is installing on laptop.
Created a windows 8.1 repair usb.
Booted USB. Ran image recovery. error 0x80042403. cleaned the disk which removed gpt. restarted computer. now cannot image drive because the image was made with bios and not UEFI. Boot settings all off and using all compatibility modes. Switched to CSM ONLY. Now the image is installing. (WHEW!)
The system image restore failed.
Error details: The processor architecture or OS version of Windows Recovery Environment is not the same as that of the computer that was backed up. For example, a backup of an Vista x64 based computer can be recovered only by using an Vista x64based version of Windows Recovery.
Make Windows 7 USB Repair
Then the newly created windows 7 usb repair would not boot on the laptop but it would boot on the desktop. Recreating it the hard way using diskpart.
Of course not that we are booting with a windows 7 USB, GPT drive cannot be used. Use Diskpart and clean to remove the GPT.
The newly recovered image did not boot and is going through windows 7 automatic startup repair.
Changed the Bios from CMS and UEFI os to CMS OS only. Windows startup repair says it may take over an hour to repair.
* may have to boot laptop into win 8 with USB and backup the bad drive to net then restore.
booted the defective drive with the win 8 repair usb: REFRESH YOUR PC: The drive where Windows is installed is locked. Unlock the drive and try again.
Somehow I got the recovery screen with Secure Boot: off; OS selection: CSM and UEFI OS; Fast Bios Mode: ON; PXE Oprom: OFF The original disk does have a GPT partition.
Primary Computer Service, Inc.