mbr2gpt Disk Validation Failed

[TammerAb]

I've been trying to get the mbr2gpt Program to work and no matter what I do it will not work

This is the command I try to run

mbr2gpt /allowFullOS /disk:1 /validate

DISKPART> list disk

Disk ### Status Size Free Dyn Gpt
-------- ------------- ------- ------- --- ---
Disk 0 Online 931 GB 0 B
Disk 1 Online 465 GB 2048 KB

Here is my disk partition information Disk 1 is the C Drive

I tried to shrink the drive by 200 mb and 2 gb it did not work.

Each time I try to validate I get the following error

C:\>mbr2gpt /allowFullOS /disk:1 /validate
MBR2GPT: Attempting to validate disk 1
MBR2GPT: Retrieving layout of disk
MBR2GPT: Validating layout, disk sector size is: 512 bytes
Disk layout validation failed for disk 1

The screenshot below shows how my disks are setup

and I'm on the correct version of windows

I tried going into recovery mode as well and I received the same error.

Here is the log when I run the tool:

2021-10-06 16:41:19, Info MBR2GPT was explicitly asked to run in full OS mode.
2021-10-06 16:41:19, Info MBR2GPT: Attempting to validate disk 1
2021-10-06 16:41:19, Info MBR2GPT: Retrieving layout of disk
2021-10-06 16:41:19, Info MBR2GPT: Initial partition information
2021-10-06 16:41:19, Info ===========================================================
2021-10-06 16:41:19, Info Partition layout for disk: 1
2021-10-06 16:41:19, Info Partition style : MBR
2021-10-06 16:41:19, Info MBR signature: 997211822
2021-10-06 16:41:19, Info Number of partitions : 2
2021-10-06 16:41:19, Info ===================PARTITION===============================
2021-10-06 16:41:19, Info Number: 1
2021-10-06 16:41:19, Info Type: 7
2021-10-06 16:41:19, Info Boot: No
2021-10-06 16:41:19, Info Recognized: Yes
2021-10-06 16:41:19, Info Style: 0
2021-10-06 16:41:19, Info Offset: 1048576
2021-10-06 16:41:19, Info Length: 499511453184
2021-10-06 16:41:19, Info Volume: \\?\Volume{3b00000-0000-0000-0000-100000000000}\
2021-10-06 16:41:19, Info Drive: C:\
2021-10-06 16:41:19, Info NT Path: \Device\HardDisk1\Partition1
2021-10-06 16:41:19, Info ===================PARTITION===============================
2021-10-06 16:41:19, Info Number: 2
2021-10-06 16:41:19, Info Type: 39
2021-10-06 16:41:19, Info Boot: No
2021-10-06 16:41:19, Info Recognized: Yes
2021-10-06 16:41:19, Info Style: 0
2021-10-06 16:41:19, Info Offset: 499514343424
2021-10-06 16:41:19, Info Length: 591396864
2021-10-06 16:41:19, Info Volume: \\?\Volume{3b00000-0000-0000-0000-604d74000000}\
2021-10-06 16:41:19, Info Drive: None
2021-10-06 16:41:19, Info NT Path: \Device\HardDisk1\Partition2
2021-10-06 16:41:19, Info ===========================================================
2021-10-06 16:41:19, Info ESP partition size will be 104857600
2021-10-06 16:41:19, Info MBR2GPT: Validating layout, disk sector size is: 512 bytes
2021-10-06 16:41:19, Error ValidateLayout: Wrong boot partition count, expected 1 but found 0.
2021-10-06 16:41:19, Error Disk layout validation failed for disk 1

2021-10-06 16:41:19, Error ValidateLayout: Wrong boot partition count, expected 1 but found 0.
2021-10-06 16:41:19, Error Disk layout validation failed for disk 1

Does anyone have any idea on how to resolve this?

[#2]

I had the same issue even I tried from Windows PE command prompt, I resolved the issue by using the third-party disk partition tool.

[#3]

Yes that is an option. But I'd like to avoid paying for a piece of Software I will only use one time.

[#4]

@TammerAb 
Please go throw the below steps:

• There should be a maximum of three primary partitions in the MBR partition table, including 100MB system partition as mentioned below:
  1. (System, Active, Primary Partition)
  2. C: (Boot, Page File, Cash Dumps, Primary Partition)
  3. D: (Primary Partition)
  
  
• You should not have any extended/logical partition, all three partitions must be primary partitions.
  
  
• If you have more than three partitions, you must delete the least important partitions after backing up the important data.
  
  
• I have done it successfully (Screenshot Attached)

mbr2gpt

The validation process has failed immediately once I added the fourth partition. (See the below screenshot)

[#5]

@SalmanAhmed 

I mean you can see in the screenshot I provided that I only have 2 partitions. Maybe you didn't see my screenshot? So your issue does not apply to me. I have no logical partitions, again the screenshot I posted shows this.

So I'm not sure if I'm missing something or you didn't look at my screenshot?

Here I reposted the screenshot in case maybe you couldn't see it.

[#6]

@TammerAb 

As I can see from the screenshot you shared, I can't see an Active partition on disk1. There is one more condition from prerequisites as below:

• One primary partition must be active, try to activate your first partition (c:) from disk 1.

I am sharing two screenshots, before and after the active partition. 

mbr2gpt tool validation result without active partitionmbr2gpt tool validation result with active partition

[#7]

@SalmanAhmed 

Tried what you suggested. It did not work

Here are the screenshots to show

[#8]

As per above screenshot, mbr2gpt tool required the OS partition as mentioned in Microsoft's official document as below:
https://docs.microsoft.com/en-us/windows/deployment/mbr-to-gpt#disk-prerequisites

[#9]

The above screenshot shows that Disk 1 is my primary partition, it contains the OS, there is no logical partition, there is only 2 partitions on that disk and the partition is active.

I've read the documentation. I do not see anything I am doing that does not match the documentation.

Apologies if I am missing something obvious but it would be helpful to me if you can point to something I am doing wrong. No need to post the documents I've read before.

[#10]

I had a similar issue even I attempted from Windows PE order brief, I settled the issue by utilizing the outsider plate segment device.

[#11]

@TammerAb 

Did you try to shrink your C: drive? I will suggest you to shrink the drive and make 1 more primary partition of 4GB at the end of the disk. Let's give it another try.

[#12]

@SalmanAhmed 

I am having the exact same problem with the exception that my primary boot disk with the OS is disk 0. It has two partitions one being the active boot partition and the second being the recovery partition. I have tried several times but it always fails.

[#13]

Hi @Blackskull,

Thanks for contacting me, as I can see from the screenshot:

• Your drive c: from disk0 has 70% free space which is more than enough
• You also have a system drive (c:) in your disk0
• You have active partition (c:)
• You don't have more than 3 partitions on disk0, which is also good.

Therefore, I'd suggest to shrink your drive c: and create another partition of 2GB. After this step try to validate the configuration by mbr2gpt tool. I hope this step will be a useful for you.

[#14]

@SalmanAhmed 

I tried shrinking the partition. It did nothing. Same issue

[#15]

Hi @TammerAb,

Please share latest screenshot from disk management console, that will be helpful to identify the point of failure.

[#16 · Accepted solution]

@SalmanAhmed 

Point of failure is Microsoft

[#17]

hello @SalmanAhmed i tried what you suggested and the program still failed. 

[#18]

Hi @Blackskull 

Please confirm that all of your 3 partitions are primary partition, the requirement says that the disk should not have any extended/logical partition.

[#19]

Hello @SalmanAhmed  2 of the partitions are primary the third is the recovery partition and I can't change it.

[#20]

Hi @Blackskull, 

Please make sure that you have 1 active partition as well, also share the screenshot of disk management console.