I use Backup Exec System Recovery to migrate to larger hard drives, to new PCs, etc.

I have painted myself into a new corner, and am looking for the way out.

Situation: I migrated to a new hard drive, but the new drive is GPT, and won't boot up. diskpart.exe does not let me manage the GPT drive (e.g. to set a partition as active), so I am stuck.

This system is a Dell XPS 8500, which we believe is UEFI capable, running the latest BIOS available for this system.

Steps I took:

  1. Plugged the new drive into box running Win 7 x64 (the box I am migrating). This is a standard MBR Windows 7 setup on a Dell desktop.
  2. Windows asked me to init the drive. I chose GPT (perhaps stupidly)
  3. I used Backup Exec System Recovery to migrate all partitions from my old drive to new drive (e.g. the hidden Windows partition and the C: partition)
  4. Disconnect old drive, plug in new drive... won't boot.
  5. Boot the backup exec CD, run diskpart, try to set the appro partition on the new drive to active.... diskpart says no thank you, it is not an MBR disk
  6. Ack, plug the old drive back in so I can boot up and get to work.

The preferred path is to understand the magic needed so I get the new drive to boot (via some unknown to me utility).

How is this done?

(I already know I can clean the target drive and redo it as MBR, but would prefer to be able to stay on the path I am on)


It won't boot because of the differences between MBR and UEFI (the standard to boot off a GPT disk). A UEFI/GPT system has an extra boot partition which contains the boot loader, you are missing this partition.

The easiest solution would be to start over and make an exact copy of the original disk. The system will just boot in MBR/legacy mode.

If you really want to try and fix it you can follow these instructions:

(I have not tested or attempted this.)

Boot off of a Windows 7 x64 Install DVD or USB stick, make sure you boot using UEFI.

Choose language and preferences, and then select Repair Your Computer -> Troubleshoot -> Advanced options -> Command Prompt Type:


Identify the boot disk where Windows is located, typing:

list disk 

Something like this should appear:

  Disk ###  Status         Size     Free     Dyn  Gpt

  --------  -------------  -------  -------  ---  ---

* Disk 0    Online          128 GB      0 B        *

Once identified, select the disk (replace with the correct number):

select disk 0

Verify the partitions:

list partition

Something similar at the info below should appear.

   Partition ###  Type              Size     Offset

   -------------  ----------------  -------  -------

   Partition 1    Primary            350 MB  1024 KB

   Partition 2    Primary            126 GB   350 MB

Delete the previous system partition:

  select partition 1

  delete partition

Create the new boot partition, Microsoft reserved partition:

  create partition EFI size=100 offset=1

  format quick fs=fat32 label="System"

  assign letter=S

  create partition msr size=128 offset=103424

If you list the partitions again, you should have ended up with something like this:

   Partition ###  Type              Size     Offset

   -------------  ----------------  -------  -------

   Partition 1    System             100 MB  1024 KB

   Partition 2    Reserved           128 MB   101 MB

   Partition 3    Primary            126 GB   229 MB

Ensure that your Windows installation is mounted, replacing 3 with the volume number of the Windows installation (usually 1):

  list volume

  select volume 3

  assign letter=C

Exit diskpart:


Generate boot partition data, replacing C: with the letter of the Windows installation (usually C:):

  bcdboot c:\windows /s s: /f UEFI

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