GPT-formatted disk. Legacy boot not support.

[krnguy1056]

Hey everyone, 

So I just got a HP Z820 from a friend and all that it was missing was a hard drive with Windows on it. 

So I took my SSD with Windows 7 installed from my PC and plugged it into the HP. 

Upon boot up, it brings me to a black screen that says:

GPT-formatted disk.

Legacy boot not support. Press any key to reboot. 

Does anyone know how to go about fixing this so that I can boot into my SSD? 

[Paul_Tikkanen]

Hi:

Go into the BIOS and disable legacy mode, but don't enable secure boot, because W7 is not compatible with secure boot.

If that doesn't work, you will need to reinstall W7 with the hard drive in the PC.

[krnguy1056]

I disabled both and it now shows:

Non-system disk or disk error.

No bootable device found.

is there anything I can do? 

EDIT: After disabling both and checking the BIOS, under Boot Order, there is a section for UEFI Boot Sources and Legacy Boot Sources. 

My SSD was under Hard Drives which was under the Legacy Boot Sources. 

My SSD is not listed under the UEFI Boot Sources. 

[Paul_Tikkanen]

You'll have to reinstall W7 in legacy mode and format the drive in MBR, not GPT.

[krnguy1056]

I believe I have my Windows 7 CD still laying around. 

What are the steps to reinstall it correctly onto my SSD? Do I do it through the BIOS upon restarting and inserting my CD? 

[Paul_Tikkanen]

You'll need the W7 installation media and the 25 character product key to reinstall windows.

Have legacy mode enabled, secure boot disabled, insert the DVD in the drive, restart the PC, TAP the ESC key to get the menu of options and from there, select the F9 boot options menu, then select the DVD drive under legacy boot sources, and press the enter key to boot from the drive.

Then see this step by step guide to install W7...

http://getintopc.com/tutorials/how-to-install-windows-7-step-by-step-method-for-beginners/

You can also order recovery media from HP if you can't find the W7 installation DVD or product key.

In the USA/Canada, call 1 (866) 724-8600 to order recovery media, and have the PC's serial number handy to give to the customer services rep.

[krnguy1056]

I will give that a try. Am I able to use my Windows 7 Home Prem key to activate Windows 10? 

So instead of using my Windows 7 CD, I just use a Windows 10 Redovery Media USB, install Windows 10 and use my Windows 7 key to activate.

Would that work? 

[Paul_Tikkanen]

Ask your friend if he ever had W10 installed on the PC by taking the free upgrade.

If so, you can just install W10, and if you are asked to enter a product key, check the 'Skip' box and W10 will install and automatically activate once you are connected to the internet.

If he did, the PC will probably have W10 Pro installed.