Forum Discussion
Shifting from BIOS to UEFI with the Windows 10 Creators Update MBR2GPT disk conversion tool
Comprehensive yet quick video overview that explains how you can safely and non-destructively convert a Windows 10 machine from legacy BIOS to UEFI disk partitioning; and how you can automate the conversion as part of your in-place upgrade process from Windows 7 to Windows 10.
I have been trying to use this converter for a few days now and always get stuck on
MBR2GPT: Trying to shrink the OS partition
Here is the log:
2018-08-01 12:16:43, Info MBR2GPT was explicitly asked to run in full OS mode.
2018-08-01 12:16:43, Info MBR2GPT: Attempting to convert disk 0
2018-08-01 12:16:43, Info MBR2GPT: Retrieving layout of disk
2018-08-01 12:16:43, Info MBR2GPT: Initial partition information
2018-08-01 12:16:43, Info ===========================================================
2018-08-01 12:16:43, Info Partition layout for disk: 0
2018-08-01 12:16:43, Info Partition style : MBR
2018-08-01 12:16:43, Info MBR signature: 3030528643
2018-08-01 12:16:43, Info Number of partitions : 1
2018-08-01 12:16:43, Info ===================PARTITION===============================
2018-08-01 12:16:43, Info Number: 1
2018-08-01 12:16:43, Info Type: 7
2018-08-01 12:16:43, Info Boot: Yes
2018-08-01 12:16:43, Info Recognized: Yes
2018-08-01 12:16:43, Info Style: 0
2018-08-01 12:16:43, Info Offset: 1048576
2018-08-01 12:16:43, Info Length: 958046142464
2018-08-01 12:16:43, Info Volume: \\?\Volume{b4a23283-0000-0000-0000-100000000000}\
2018-08-01 12:16:43, Info Drive: C:\
2018-08-01 12:16:43, Info NT Path: \Device\HardDisk0\Partition1
2018-08-01 12:16:43, Info ===========================================================
2018-08-01 12:16:43, Info ESP partition size will be 104857600
2018-08-01 12:16:43, Info MBR2GPT: Validating layout, disk sector size is: 512 bytes
2018-08-01 12:16:43, Info BCD: Opening store. Flags: 0x0
2018-08-01 12:16:43, Info BCD: Store path: "\??\GLOBALROOT\device\harddisk0\partition1\Boot\BCD"
2018-08-01 12:16:43, Info BCD: Loaded hive at BCD00000000
2018-08-01 12:16:43, Info BCD: Opening object {9dea862c-5cdd-4e70-acc1-f32b344d4795}
2018-08-01 12:16:43, Info FindOSPartitions: Default boot entry: {6B5EAFC2-954A-11E8-888E-001A7DDA7113}
2018-08-01 12:16:43, Info BCD: Opening object {6b5eafc2-954a-11e8-888e-001a7dda7113}
2018-08-01 12:16:43, Info VERBOSE: Device path: \Device\HarddiskVolume5
2018-08-01 12:16:43, Info VERBOSE: Dos path: \\?\GLOBALROOT\Device\HarddiskVolume5
2018-08-01 12:16:43, Info FindOSPartitions: Volume name for the default boot entry: \\?\Volume{b4a23283-0000-0000-0000-100000000000}\
2018-08-01 12:16:43, Info BCD: BcdGetElementDataWithFlags: Failed to open key.Object: {6b5eafc2-954a-11e8-888e-001a7dda7113} Type: 14000008 Status: c0000034
2018-08-01 12:16:43, Info FindOSPartitions: No Recovery sequence found.
2018-08-01 12:16:43, Info FindOSPartitions: Default boot entry locale: en-us
2018-08-01 12:16:43, Info Bitlocker protection for C:\ is either off or suspended.
2018-08-01 12:16:43, Info Unique ID recap for volumes:
2018-08-01 12:16:43, Info Volume name: \\?\Volume{b4a23283-0000-0000-0000-100000000000}
2018-08-01 12:16:43, Info Unique ID size: 12
2018-08-01 12:16:43, Info MBR2GPT: System partition cannot be removed in full OS mode, leaving it untouched.
2018-08-01 12:16:43, Info MBR2GPT: Trying to shrink the OS partitionI have a SanDisk SSD
I noticed that when I try to shrink Volume via Disk management it just hangs on the next window, the Activity Monitor shows a Service Host: Disk Defragmenter / Optimize drives process tat is using 10% CPU, has a growing memory usage as well as about 10MB/s disk usage
The exact same thing happens when the MBR2GPT process is "stuck" on Trying to shrink the OS partition
I partitioned the disk using a 3rd party software and create a 2GB Unallocated sector and tried again, same issue.I also remove the 2 recovery partition on the drive. (I have a USB disk with the windows recovery system)
I am not sure what is going on, but I would really hate to do a complete wipe of the drive and start from scratch.I welcome any ideas at this point.
Do you have the same problem when running MBR2GPT from WinPE? Chances are, you have something running in the full OS that is causing the issue and this is why it is recommended to run MBR2GPT in WinPE.
I was finally able to complete the process.
I did this through the OS, not in PE.
The issue is really with how the process went on my SSD.
It was analyzing it for a while, like a good hour.
But, before the last time I tried it, when it worked, I used the Defragmenter tool to "optimize" my SSD, then it did the same thing, but now it worked. I can post the logs if it is going to help anyone.
I did have a boot problem, my BCD was effed up.
For this I did you WinPE and had to do the assign a letter to the EFI partition, then do the bcdboot c:\windows /s e: command to get the BCD stuff from the installed windows to the EFI partition, now it boots and switched the GPT so all is well.
I gave it some time and now it failed:
2018-08-01 12:52:50, Info MBR2GPT was explicitly asked to run in full OS mode.
2018-08-01 12:52:50, Info MBR2GPT: Attempting to convert disk 0
2018-08-01 12:52:50, Info MBR2GPT: Retrieving layout of disk
2018-08-01 12:52:50, Info MBR2GPT: Initial partition information
2018-08-01 12:52:50, Info ===========================================================
2018-08-01 12:52:50, Info Partition layout for disk: 0
2018-08-01 12:52:50, Info Partition style : MBR
2018-08-01 12:52:50, Info MBR signature: 3030528643
2018-08-01 12:52:50, Info Number of partitions : 1
2018-08-01 12:52:50, Info ===================PARTITION===============================
2018-08-01 12:52:50, Info Number: 1
2018-08-01 12:52:50, Info Type: 7
2018-08-01 12:52:50, Info Boot: Yes
2018-08-01 12:52:50, Info Recognized: Yes
2018-08-01 12:52:50, Info Style: 0
2018-08-01 12:52:50, Info Offset: 1048576
2018-08-01 12:52:50, Info Length: 957941284864
2018-08-01 12:52:50, Info Volume: \\?\Volume{b4a23283-0000-0000-0000-100000000000}\
2018-08-01 12:52:50, Info Drive: C:\
2018-08-01 12:52:50, Info NT Path: \Device\HardDisk0\Partition1
2018-08-01 12:52:50, Info ===========================================================
2018-08-01 12:52:50, Info ESP partition size will be 104857600
2018-08-01 12:52:50, Info MBR2GPT: Validating layout, disk sector size is: 512 bytes
2018-08-01 12:52:50, Info BCD: Opening store. Flags: 0x0
2018-08-01 12:52:50, Info BCD: Store path: "\??\GLOBALROOT\device\harddisk0\partition1\Boot\BCD"
2018-08-01 12:52:50, Info BCD: Loaded hive at BCD00000000
2018-08-01 12:52:50, Info BCD: Opening object {9dea862c-5cdd-4e70-acc1-f32b344d4795}
2018-08-01 12:52:50, Info FindOSPartitions: Default boot entry: {6B5EAFC2-954A-11E8-888E-001A7DDA7113}
2018-08-01 12:52:50, Info BCD: Opening object {6b5eafc2-954a-11e8-888e-001a7dda7113}
2018-08-01 12:52:50, Info VERBOSE: Device path: \Device\HarddiskVolume5
2018-08-01 12:52:50, Info VERBOSE: Dos path: \\?\GLOBALROOT\Device\HarddiskVolume5
2018-08-01 12:52:50, Info FindOSPartitions: Volume name for the default boot entry: \\?\Volume{b4a23283-0000-0000-0000-100000000000}\
2018-08-01 12:52:50, Info BCD: BcdGetElementDataWithFlags: Failed to open key.Object: {6b5eafc2-954a-11e8-888e-001a7dda7113} Type: 14000008 Status: c0000034
2018-08-01 12:52:50, Info FindOSPartitions: No Recovery sequence found.
2018-08-01 12:52:50, Info FindOSPartitions: Default boot entry locale: en-us
2018-08-01 12:52:50, Info Bitlocker protection for C:\ is either off or suspended.
2018-08-01 12:52:50, Info Unique ID recap for volumes:
2018-08-01 12:52:50, Info Volume name: \\?\Volume{b4a23283-0000-0000-0000-100000000000}
2018-08-01 12:52:50, Info Unique ID size: 12
2018-08-01 12:52:50, Info MBR2GPT: System partition cannot be removed in full OS mode, leaving it untouched.
2018-08-01 12:52:50, Info MBR2GPT: Trying to shrink the OS partition
2018-08-01 13:24:29, Info MBR2GPT: Partition final size is: 957836427264
2018-08-01 13:24:29, Info MBR2GPT: Creating the EFI system partition
2018-08-01 13:24:29, Info Initializing VDS service
2018-08-01 13:24:29, Info Obtaining the VDS disk interface
2018-08-01 13:24:29, Info Retrieving the VDS disk properties
2018-08-01 13:24:29, Error PreparePartition: cannot format partition. Error: 0x00000000, async error: 0x80070057[gle=0x000036b7]
2018-08-01 13:24:29, Error Cannot create EFI system partition. Error: 0x000036B7[gle=0x000036b7]
2018-08-01 13:24:29, Info MBR2GPT: Partition information at error point
2018-08-01 13:24:29, Info ===========================================================
2018-08-01 13:24:29, Info Partition layout for disk: 0
2018-08-01 13:24:29, Info Partition style : MBR
2018-08-01 13:24:29, Info MBR signature: 3030528643
2018-08-01 13:24:29, Info Number of partitions : 1
2018-08-01 13:24:29, Info ===================PARTITION===============================
2018-08-01 13:24:29, Info Number: 1
2018-08-01 13:24:29, Info Type: 7
2018-08-01 13:24:29, Info Boot: Yes
2018-08-01 13:24:29, Info Recognized: Yes
2018-08-01 13:24:29, Info Style: 0
2018-08-01 13:24:29, Info Offset: 1048576
2018-08-01 13:24:29, Info Length: 957836427264
2018-08-01 13:24:29, Info Volume: \\?\Volume{b4a23283-0000-0000-0000-100000000000}\
2018-08-01 13:24:29, Info Drive: C:\
2018-08-01 13:24:29, Info NT Path: \Device\HardDisk0\Partition1
2018-08-01 13:24:29, Info ===========================================================
2018-08-01 13:24:29, Info MBR2GPT-undo: Extending back the OS partition
2018-08-01 13:24:29, Info MBR2GPT: Conversion failed
This tool is very beta, poor coding, new error:
cannot rely on this space
<z:row Cls="D" Sev="50331648" Maj="Def" Min="Def" LN="4099" Fil="" Fun="pExecuteConversion" Uid="50331648" Msg="MBR2GPT: Partition final size is: 248640438272 (initial size was 248640438272), cannot rely on this space" PID="14424" TID="14612" Con="" Exe="C:\WINDOWS\system32\MBR2GPT.EXE" Mod="MBR2GPT.EXE" Err="0" MD="" DT="2018-04-10T20:48:51"/>
Validation is succeffull.
Just done this on one of our work machines. If this works it'll save us bloody hours so cheers MS. One question though it seems to have gotten to "Fixing drive letter mapping" and stopped. Checking everything else it seems fine, disk converted , lovely... so is it safe to restart and change the BIOS/UEFI options or does this take a dam sight longer than the video hinted at?
Up to 40 minutes now.For the people who are getting the following error when validating:
Cannot find OS partition(s) for disk X
First make sure you have the correct disk selected with the Windows installation.If this is the case there is probably something wrong in your BCD configuration. If you have a simple single boot system, you can easily rebuild it from a elevated prompt with:bcdboot.exe X:\Windows
After that it should validate just fine (it did in my case).X is dependent on your system. In most cases 0 and C- Thank you! This was exactly what I needed to do.
Hi,I can't convert it from MBR to GPT.
This is the error:
MBR2GPT: Attempting to validate disk 0
MBR2GPT: Retrieving layout of disk
MBR2GPT: Validating layout, disk sector size is: 512 bytes
Disk layout validation failed for disk 0I Just resolved the validation issue.
basically you must not have more than three partitions and not any free space left on the hard drive.
if you check the list of partition on DISKPART you will see that even the free space is listed as a partition.
you can use tools like disk manager (built-in windows) or minitool to resize the current partitions to take up the left over free space then validate mbr2gpt again.
hopefully it works for you too :)let me know
Here is what my HD looks like using DISKPART:
DISKPART> list volume
Volume ### Ltr Label Fs Type Size Status Info
---------- --- ----------- ----- ---------- ------- --------- --------
Volume 0 E DVD-ROM 0 B No Media
Volume 1 C 790 SSD NTFS Partition 449 GB Healthy System
Volume 2 D Recovery NTFS Partition 15 GB Healthy
Volume 3 RAW Partition 856 MB Healthy Hidden
Volume 4 RAW Partition 455 MB Healthy HiddenAnd the attached PDF shows what it looks like using the Disk Management extension of the Computer Management console.
How would you suggest dealing with these partitions in order to be able to sucessfully run MRS2GPT?
I understand that the MBR2GRT.exe will support versions of Win 10 previous to 1703 and should work when booted from a Win PE 1703 disk.
So I downloaded & install Windows ADK 1703 & made a Win PE disk. I booted from that disk and ran MBR2GPT /validate and the result was "unable to validate disk." Any ideas? It's a 500gb disk with about 90gb free. Is free space the problem?
Larry Hess CAP | Albuquerque, NM | www.LarryHesscpa.com
Tried a lot.
I am getting an "unrecognized partition error".
This is my partition setup.
I have attached the log files below.
Somebody please help :(
- Use third party tool to convert the logical partition to primary partition
There is a partition on the disk MBR2GPT doesn't like. Try running the following diskpart commands:
DISKPART> select disk 0
DISKPART> list partition
.
.
.
DISKPART> select partition 1
DISKPART> detail partition
.
.
.
(repeat for each partition)
You should be able to see which one is causing issues.
Mike, I hope you will spend a few minuttes looking over this, as I can't figure it out on my own.
Is the attached information sufficient?
Thanks in advance.
Diskpart overviewMBR2GPT validation and result
- I accidentally deleted the MSR partition from the drive when downloading Windows. Should I recreate the MSR? If so, does anyone know how to do it?
Does this work for Home or Pro versions of Windows 10? Or just enterprise?
- Pro working, so home must work too.
