By Cherry / Last Updated May 5, 2023


"I have a 3 TB hard drive, and I installed it on my Windows 7 computer. There are four parts on my hard drive, the system reserved partition, the system partition, and two unallocated space, and I want to use the unallocated space to create some new partitions to store different files. However, when I right-click the last unallocated space, it showed gray like the following picture displayed (the first unallocated space is valuable)."

It was too bad that the New Simple Volume, New Spanned Volume, New Striped Volume, New Mirrored Volume, and New RAID-5 Volume greyed out so that you cannot create a new partition with the unallocated space. And some users said that his 3 TB disk only used 2 TB like the following screenshot, and he tried to use the New Simple Volume to create a new partition to use it. However, he found the option greyed out.

New Simple Volume greyed out

With all these problems, how could you make full use of your disk?

Why is "New Simple Volume" greyed out?

As the scenario said, the first unallocated space is in the normal state, while the options in the second unallocated space are grayed out. Why? Most users may know that Windows operating system supports both MBR and GPT disks, and the two disk types have their characteristics to affect PC storage performance.

MBR, the abbreviation of Master Boot Record, only supports the capacity of up to 2 TB, and you can only create up to 4 primary partitions, once you want to create more partitions for different files, you have to convert one primary partition to extended partition to create logical partitions (The number of logical partitions on MBR disk is unlimited).

GPT, the short of GUID Partition Table, breaks out the limitation of MBR. It supports more than 2 TB capacity and you can create 128 partitions on a GPT disk in Windows OS.

Considering the problems in the scenario, the problem is clear that your hard drive is MBR that can only use up to 2 TB. That’s why the New Simple Volume greyed out beyond 2 TB in Windows Disk Management.

How to solve New Simple Volume greyed out?

To solve the New Simple Volume greyed out, you should change the MBR into a GPT disk so that the part beyond 2 TB can be available. And here provides you with two different ways to convert MBR to GPT disk.

Method 1. With built-in Disk Management

Disk Management is a built-in disk manager of the Windows system.

Step 1. Right-click This PC -> Manage -> Disk Management.

Step 2. Right-click the 3TB hard drive and select “Convert to GPT Disk”, then follow the guidance to finish this conversion.

Convert to GPT

However, when you want to use it to convert a disk from MBR to GPT if there are some files on the 3TB hard drive, you have to delete all the data on the disk. Because Disk Management can only convert an empty MBR into GPT. Otherwise, you’ll find "Convert to GPT greyed out".

Convert to GPT greyed out

Method 2. With AOMEI Partition Assistant

AOMEI Partition Assistant Professional is a powerful disk manager. You can use it to manage your disk for Windows XP/Vista/7/8/8.1/10/11. What’s the most important thing is it can convert MBR to GPT without losing data, no matter the target disk is a system disk or a data disk, all data is safe. The operations are also quite user-friendly, only 3 steps, you can finish the task.

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Now, let's see the details.

Step 1. Install and launch AOMEI Partition Assistant, you will see the main situation of your hard drive.

Step 2. Right-click the disk no matter if there are partitions on it or not, and select “Convert to GPT".

Convert to GPT

Step 3. It will pop out a window so that you can ensure whether you’d like to convert it. Click "OK".


Step 4. Click “Apply” on the toolbar. Then, it will convert the MBR disk to a GPT disk.


After converting the MBR disk to a GPT disk, you can make full use of your 3 TB hard drive. The New Simple Volume of Disk Management would not be grayed out, so you can use it to create a new partition or extend the partition before. You can also use the AOMEI Partition Assistant to create partitions, merge unallocated space, and so on.

Final lines

"New Simple Volume" greyed out is not a big problem, hope you can solve this problem with the methods we list. As a versatile disk management tool, AOMEI Partition Assistant can clone disk, migrate OS to another disk, extend C drive... And if you have a Server system, you can choose the Server Edition to optimize your device.