GPT conversion problem

[Cartesian214]

I recently built a new Desktop using an Asus Sabertooth Z77 motherboard, and I'm trying to install a 3tb Seagate Barracuda drive using GPT format.

Unfortunately the Windows Disk Management utility gives it a system reserved partition by default, which I cannot remove. The option to convert to GPT is grayed out.

I have my OS on a separate drive, so there shouldn't be a need for a reserved partition. I tried uninstalling the drive and restarting, but Windows just put it right back. My next step was to use diskpart and the "Convert GPT" command, but it says it is not convertible. Clearly this isn't true, as it's a brand new 3tb drive. What can I do?

The diskpart error reads

Virtual Disk Service Error:
The specified disk is not convertible. CDROMs and DVDs are examples of disks that are not convertible

 

[Cerb]

Unfortunately the Windows Disk Management utility gives it a system reserved partition by default, which I cannot remove. The option to convert to GPT is grayed out.

It's already GPT, so of course you can't convert it.

I have my OS on a separate drive, so there shouldn't be a need for a reserved partition.

Yes, there is a need for a reserved partition.

Q. What is a Microsoft Reserved Partition (MSR)?

A.

The Microsoft Reserved Partition (MSR) reserves space on each disk drive for subsequent use by operating system software. GPT disks do not allow hidden sectors. Software components that formerly used hidden sectors now allocate portions of the MSR for component-specific partitions. For example, converting a basic disk to a dynamic disk causes the MSR on that disk to be reduced in size and a newly created partition holds the dynamic disk database.

Q. What disks require an MSR?

A. Every GPT disk must contain an MSR. The order of partitions on the disk should be ESP (if any), OEM (if any) and MSR followed by primary data partition(s). It is particularly important that the MSR be created before other primary data partitions.

 

[Cartesian214]

ah, thanks for the explanation. But if it's already in GPT format, how come I can't create a partition larger than 2048gb?

 

[Cerb]

ah, thanks for the explanation. But if it's already in GPT format, how come I can't create a partition larger than 2048gb?

That's a good question. It should default to creating a ~2.7TB data partition. And, that partition, you should be able to delete and recreate.

 

[Goros]

It's because the system defaulted it to MBR and locked it when it created the system reserve. You need to go into disk manager and delete the partitions completely so it's just a raw drive.

Then, switch it to GPT and format it.

When it's in GPT, the box says "convert to MBR". When it's MBR, it says "convert to GPT". It's grayed out because of the reserve. System should have put the reserve on the OS drive, not sure why it didn't.

 

[Cartesian214]

but the option to delete the partition is grayed out as well... how can I get it into a raw state when Windows automatically partitions it?

One thing I tried was to uninstall the drive from the device manager, but when I restarted the computer it just reinstalled it before I could do anything

----TIME PASSES----

Okay so I am looking at the drive/partition in DiskPart and trying to delete it. It says "Format is not allowed on the current boot, system, pagefile, crashdump, or hibernation volume"

Is Windows using this drive for something? Because it shouldn't be. I did try to create a partition when I was installing windows, but gave up after it presented me with the 2048mb option.

----MORE TIME PASSES----

I have found the problem! Somehow Windows (you lovable rogue, you) decided to make this my boot drive... even though my operating system and everything else is on the SSD.

When in the Disk Utility, it lists the SSD as Disk 0 with the following description

223.57 GB NTFS
Healthy (Boot, Page File, Crash Dump, Primary Partition)

Followed by the Barracuda:

System Reserved
214 MB NTFS
Healthy (System, Active, Primary Partition)

After going into my BIOS I found the boot order listed the Barracuda first, so I tried disabling it. My computer refused to boot. So I have concluded that, despite much evidence to the contrary, the barracuda is my Boot Drive.

How can I change this?

----EVEN MORE TIME PASSES----

According to EasyBCD, the SSD (C drive) is my boot drive. When I enter the BIOS and select the SSD, it fails. When I select the Barracuda as my boot device, it boots normally. What the heck!?

 

[Goros]

You need to put it back the way it was, back everything you need up, and wipe/reformat both drives from scratch. In windows setup you can choose to delete partitions. Once you delete the partition on the 3tb drive, don't re-create it until you have windows 100% installed and functional on your OS drive.

Good luck.

 

[Cerb]

I did try to create a partition when I was installing windows

Backup and re-install. Don't have multiple drives connected when installing Windows. Install windows with only the OS drive hooked up, then after it's up and running, connect and configure the data drive.

 

[Cartesian214]

Ouch, I was afraid you were going to say that. Looks like I have a lot of work ahead of me.

Do you think it would work if I partitioned the Data drive and moved all my stuff onto that, then reformatted the SSD/reinstalled Windows, then moved stuff back and reformatted the Data drive afterward?

 

[Cerb]

Ouch, I was afraid you were going to say that. Looks like I have a lot of work ahead of me.

Do you think it would work if I partitioned the Data drive and moved all my stuff onto that, then reformatted the SSD/reinstalled Windows, then moved stuff back and reformatted the Data drive afterward?

If all of your current data can fit on the SSD, then yes, that should work just fine.