Computers & Electronics

HELP! How to revert drive back to Legacy from UEFI mode

  • Last Updated:
  • Apr 29th, 2019 8:50 am
Deal Expert
User avatar
Dec 23, 2003
18021 posts
7061 upvotes
Toronto

HELP! How to revert drive back to Legacy from UEFI mode

I have an old Asus K53E laptop with a Samsung SSD on Windows 10 and thought I could convert the drive from Legacy Mode to UEFI mode following this video clip:

After running the mbr2gpt utility, I went into the BIOS and changed the setting from Legacy to UEFI mode. I restarted the PC and now I just get a black screen with a cursor flashing on the top left of the screen. I tried flipping back to Legacy and reboot and the same thing. The drive no longer loads windows.

Can someone please suggest how to change the drive BACK to Legacy? I think what I need to do is the following:

- remove SSD drive from laptop
- put the drive in some SATA to USB dock
- go to another computer and hook up this drive to it
- run some utility to convert the drive back to Legacy mode
- take the drive out of the dock and put it back in the laptop
- verify that boot settings in the laptop bios is in legacy mode
- try booting off the SSD and pray that is works

Can someone please suggest a utility that will let me convert a drive back to Legacy mode? Would this utility work or is there others that are better? https://www.disk-partition.com/gpt-mbr/ ... 4348i.html

I really don't want to have to format/reinstall everything all over again.

Thanks


Update: I purchased the pro version of https://www.disk-partition.com/partitio ... v_products and converted the drive back to MBR mode and I still have the same issue of not booting (black screen with a cursor flashing in the top left corner).
6 replies
Sr. Member
Nov 14, 2008
857 posts
325 upvotes
if after all this you go back to legacy, what was the point?
1.make sure all your files are backed up

Try booting with windows install usb/recovery and doing the windows 10 steps for efi
https://www.dell.com/support/article/ca ... pc?lang=en

otherwise the quickest option is probably
reboot and reinstall windows in uefi mode.

If no windows install disk, get windows 10 here
https://www.microsoft.com/en-ca/softwar ... /windows10

and use rufus
Deal Expert
User avatar
Jun 27, 2004
15215 posts
4405 upvotes
Vancouver.bc.ca
Macrium Reflect can repair Windows boot errors, if you want to try that.

It's on Hiren's Boot .iso (1.2GB download) -> https://www.hirensbootcd.org
(never tried Hiren's myself, although I have used Macrium to repair Win7 boot errors)
Deal Addict
Feb 24, 2007
4233 posts
1220 upvotes
I believe you were trying to enable the Fast Boot for Windows 10 by converting the drive to UEFI. I think there's something your video card itself or driver has to support that also in order to use the Fast Boot.
Might work if you tried to convert the drive back to MBR.
FS : Promise NS4300N NAS,Linksys RE400W,E5151,HBB1,VIVOTab RT,MemoPad 8
Deal Addict
Apr 29, 2018
3474 posts
2697 upvotes
Vancouver
Yeah, that conversion requires a reformat. Best to revet back to UEFI in BIOS and then run the Windows Installer on the same drive. Windows will find and offer to "upgrade" the old install, keeping all your data safe, and fix things
Can't Stop. Won't Stop. Game Stop
Deal Expert
Feb 29, 2008
30106 posts
5547 upvotes
Montreal
Just running mbr 2 gpt is not enough. You have to create an EFI partition, and install the boot loader to that partition.

I've never done this on windows, so someone else can chime in on the steps.

Also remember that MBR can't boot from partitions larger than 2TB under windows.
Deal Expert
User avatar
Dec 23, 2003
18021 posts
7061 upvotes
Toronto
Avatar wrote: I believe you were trying to enable the Fast Boot for Windows 10 by converting the drive to UEFI. I think there's something your video card itself or driver has to support that also in order to use the Fast Boot.
Might work if you tried to convert the drive back to MBR.
I have the built in Intel video card on the system. It is the K53E Asus.

I just ordered a new SSD and will install windows 10 from scratch on it and set it to UEFI

Top

Thread Information

There is currently 1 user viewing this thread. (0 members and 1 guest)