MBR2GPT Disk layout validation failed for disk 1

[Puncake]

I am using a 4TB HDD as a storage drive on my pc, with a 500GB SSD for the os and other programs. I am only able to partition 2TB of my HHD due to it having a MBR partition style, and would like to convert it to GPT so I can use all of its available space. The 2TB partition is almost full, and only has 67GB remaining, which is why I am trying to convert it.

After using the command "mbr2gpt /validate /disk:1 /allowFullOS" I get the message "Disk layout validation failed for disk 1"

How can I fix this?

 

[RealBeast]

That tool only works for the system disk, it will not work for just a storage disk.

You can either backup the data elsewhere and then reinitialize (that will delete all the data) or you can spend about $30 for a pay version of EaseUS Partition Manager or similar software that will do the conversion with data on the drive.

In any case it is always best to backup any important data.

 

[ArtPog]

Actually you may be in luck. AFAIK, all (or virtually all) of the third-party freely-available partition management programs, e.g., MiniTool Partition Wizard, AOMEI Partition Assistant, etc., possess the capability of converting a secondary storage drive from MBR to GPT as long as pointed out by RealBeast the drive does NOT contain an OS. And his advice is sound as to backing up data that is important to you BEFORE undertaking the conversion process. As we all too well know, s#*! happens.

 

[photonboy]

Actually you may be in luck. AFAIK, all (or virtually all) of the third-party freely-available partition management programs, e.g., MiniTool Partition Wizard, AOMEI Partition Assistant, etc., possess the capability of converting a secondary storage drive from MBR to GPT as long as pointed out by RealBeast the drive does NOT contain an OS. And his advice is sound as to backing up data that is important to you BEFORE undertaking the conversion process. As we all too well know, s#*! happens.

??
actually, he said MBR2GPT ONLY works on the OS drive and NOT for secondary/storage drives.

 

[ArtPog]

photonboy:
When you refer to "he" I assume you're referring to the 12/9/17 response of RealBeast, are you not?

You might want to carefully read my response re that portion concerning the utilization of the Win 10 MBR2GPT disk conversion tool.

1. I fully agree that the MBR2GPT disk conversion process can be successful in a Win 10 environment when the boot drive contains the Win 10 OS. There is no dispute about that.

2. I further agree that a system's MBR-partitioned secondary drive that has been used for storage and DOES NOT contain the Win 10 OS (as apparently in the OP's case) cannot be converted to the GPT-partitioning scheme via the MBR2GPT disk conversion tool. There is no dispute about that.

And that is why I recommended that the OP might want to utilize a FREELY-AVAILABLE third-party partition management program, e.g., MiniTool Partition Wizard, AOMEI Partition Assistant, etc., which possess the capability of converting a secondary storage drive from MBR to GPT (as long as pointed out by RealBeast) the drive does NOT contain an OS. There would be NO COST to the OP using that option and it's a simple operation for the PM program to undertake (although it's ALWAYS wise for a user to back up the drive's data BEFORE undertaking this conversion process (as RealBeast points out).

NOW...
3. If an MBR-partitioned secondary drive DOES CONTAIN AN OS - even though the drive is not being utilized as a system (boot) drive in its present environment - the MBR2GPT disk conversion tool WILL carry out the conversion process on that secondary drive. (We have found the third-party PM programs will balk at doing so when they detect an OS on the drive.)

 

[RealBeast]

photonboy:
When you refer to "he" I assume you're referring to the 12/9/17 response of RealBeast, are you not?

You might want to carefully read my response re that portion concerning the utilization of the Win 10 MBR2GPT disk conversion tool.

1. I fully agree that the MBR2GPT disk conversion process can be successful in a Win 10 environment when the boot drive contains the Win 10 OS. There is no dispute about that.

2. I further agree that a system's MBR-partitioned secondary drive that has been used for storage and DOES NOT contain the Win 10 OS (as apparently in the OP's case) cannot be converted to the GPT-partitioning scheme via the MBR2GPT disk conversion tool. There is no dispute about that.

And that is why I recommended that the OP might want to utilize a FREELY-AVAILABLE third-party partition management program, e.g., MiniTool Partition Wizard, AOMEI Partition Assistant, etc., which possess the capability of converting a secondary storage drive from MBR to GPT (as long as pointed out by RealBeast) the drive does NOT contain an OS. There would be NO COST to the OP using that option and it's a simple operation for the PM program to undertake (although it's ALWAYS wise for a user to back up the drive's data BEFORE undertaking this conversion process (as RealBeast points out).

NOW...
3. If an MBR-partitioned secondary drive DOES CONTAIN AN OS - even though the drive is not being utilized as a system (boot) drive in its present environment - the MBR2GPT disk conversion tool WILL carry out the conversion process on that secondary drive. (We have found the third-party PM programs will balk at doing so when they detect an OS on the drive.)

Totally agree, and you both obviously know what you are doing, which is the difference.

For posters that don't seem to be knowledgeable I often simplify answers a bit (sometimes quite a bit) just giving them the essentials to keep it brief, like not mentioning that an OS on a secondary disk allows use of MBR2GPT. I am convinced that they would screw it up. 😉 And I'm sure that you guys do the same as I've seen many of your threads.

Finally, thanks for all that you both do to make TH a great resource!

(and none of this is directed at the OP but it is just my habit to keep it simple until they show that they want to walk out on the thin ice)

 

[photonboy]

Okay fine.
The wording was confusing though as RealBeast was specifically referring to MBR2GPT when he said:

"That tool only works for the system disk..."

Then Artpog said:
"as long as pointed out by RealBeast the drive does NOT contain an OS"

In retrospect maybe Artpog is referring to the 2nd sentence ("data on the drive..."?).

I believe you both know what you are talking about but if someone stumbled on this I didn't want them confused thinking MBR2GPT was suitable for non-OS drive conversions.

Probably no point in looking at this any further. A simple mistake on somebody's part; possibly mine.

 

[RealBeast]

HERE is the detail of the tool that I probably should have linked in my first post in case someone wanted more information.

 

[ArtPog]

I am using a 4TB HDD as a storage drive on my pc, with a 500GB SSD for the os and other programs. I am only able to partition 2TB of my HHD due to it having a MBR partition style, and would like to convert it to GPT so I can use all of its available space. The 2TB partition is almost full, and only has 67GB remaining, which is why I am trying to convert it.

After using the command "mbr2gpt /validate /disk:1 /allowFullOS" I get the message "Disk layout validation failed for disk 1"

How can I fix this?

So were you finally able to convert your MBR-partitioned secondary 4 TB drive to the GPT-partitioning scheme using a partition management program or some other program?