Windows 10: Add Windows drive with MBR to a UEFI System

Hi!I have a booteable hard disk by mean MBR with Windows Server 2019.I want to add that hard disk to a system with UEFI which has Linux installed with its boot loader /boot/efi partition.How can I add the Windows drive in order to get adual boot sistem?Thank you in advance

:)

 

Cannot convert SSD drive from legacy (MBR) to UEFI (GPT) because of the System-reserved partition

Maybe someone covered this earlier in the thread but a Legacy Windows install will not boot to a GPT configured drive. You need to use UEFI for that and UEFI will not boot to a MBR configured drive.

So, unless you have a UEFI capable system you need to stay with MBR for the Boot drive...

 

MBR to UEFI conversion

In addition to the good explanation that Greg provided, I would like to add a technical distinction:

The UEFI is akin to firmware while the MBR is a partitioning method. So you would compare the UEFI to the BIOS, and the MBR to the GPT. You wouldn't speak of converting MBR to UEFI.

I said that the UEFI is akin to firmware, because it's not really firmware. The BIOS really is firmware, because it resides on a chip on the motherboard. But the UEFI is programmable software that sits between the computer’s hardware and the operating
system.

The only compelling reason to convert your hard drive from MBR to GPT is if you need to have more than 4 primary partitions on the drive. MBR is limited to 4 primary partitions. And then, since GPT can't be run from the BIOS, you would need to use the UEFI.

The UEFI has many technical improvements over the BIOS, to be sure, but considering the uncertainty inherent in converting old hardware, there isn't really a good reason to attempt converting from BIOS to UEFI other than the satisfaction in pulling off a
complicated maneuver.

 

Stuck in MBR in UEFI, please help

I got it working, if anyone is in the same boat. My error was trying to convert the drive to GPT after cloning the drive.

This should help anyone who is stuck in MBR in UEFI.

Steps:

1) Make sure you have your data/windows partition backed up to another drive (in my case, it was my original SATA drive).
2) Boot to recovery media, go to command line
3) Use DISKPART to Clean the drive, then Convert GPT
4) I then followed the steps here. Props to Raunak Dutta. https://answers.microsoft.com/en-us...ning-mbr/5753c8e2-6c39-4c2d-b560-82cd52e8aa17
5) Shut down and remove all other drives.
6) It still wouldn't boot, and I tried Microsoft startup repair, that wouldn't work either. But what did work was a Macrium Recovery Disk. Boot into this disk in UEFI mode and hit the Fix Windows Startup Problems function. Let it repair
7) Reboot in UEFI into your drive. It should now start booting, and in my case it ran a cycle of Chkdsk automatically (I let it run).
8) Mine was perfect from there! GPT/UEFI/NVME/Z87. I'm using it now to type this out. 3000+ MB/s read/write.

P.S. I also used UEFITool to clean up/sort/rename the UEFI entries to delete the duplicates and make it clearer what was what. The top boot priority is the EFI partition on the NVME drive.