How to Partition 4TB Hard Drive in Windows 10/8/7 with the Correct Way?

February 13, 2019

When you meet the problem that cannot partition 4TB hard drive totally, you can try to use AOMEI Partition Assistant to help you get full use of the 4TB hard drive safely and simply.

The Scenario

"Hi, I have a problem for partitioning 4TB hard drive. Here it is, I was trying to install a 4TB hard drive into a new PC. To avoiding the problem that cannot install Windows on a partition of more than 2TB, I specially installed a 140GB hard drive just for Windows, planning to use the 4TB hard drive for storage. However, I still can only create a 2TB partition on the big drive. It would not allow me to partition the rest of the unused space."

Cannot Partition 4TB Hard Drive

The Problem

As the scenario said, the hero cannot partition more than 2TB hard drive on his 4TB hard drive. Actually, many users have met the similar problems. To partition a 4TB hard drive, you need to know the basic requirements of 4TB hard drive in Windows.

No matter what Windows operating system you are using, you need to know there are two kinds of hard drive disk: MBR disk and GPT disk. MBR is the abbreviation of Master Boot Record, which use the standard BIOS, supports up to 2TB capacity. And the GPT (GUID Partition Table) disk which uses UEFI (unified extensible firmware interface), supports disk with more than 2TB capacity. thus, you cannot partition the 4TB hard drive may because it is MBR disk. So, you can solve the problem by converting the MBR disk to GPT disk.

The Solutions

We have already know that the MBR can only support up to 2TB disk, beyond the 2TB, the space could be invalid. Even it shows as unallocated space at the end of the disk, you cannot partition, either--the New Simple Volume greyed out that you cannot create partition with it, or other operations. Then, check whether your mother board is UEFI compatible. Thus, convert MBR disk to GPT disk is an effective way to solve the problem.

As Windows Disk Management can only convert an empty MBR disk to GPT disk, you will find that “Convert to GPT Disk” option is grayed out too.

Convert to GPT Greyed out

Thus, to convert MBR disk to GPT disk without losing data, here we highly recommend you AOMEI Partition Assistant to convert the disk. AOMEI Partition Assistant is a professional disk manager that you can use to convert disk between MBR and GPT without destroying any data in a few clicks.

Note: Although AOMEI Partition Assistant can help you convert MBR to GPT without losing data, you need to backup disk in advanced to prevent ant accident which may cause data loss.

Step1. Download, install and launch the AOMEI Partition Assistant Standard edition. The basic environment of your hard drive will display in your eyes. You can see the 4TB partition only used 2TB and beyond 2TB, it is shown as unallocated space, and your cannot use it. To convert the MBR disk into GPT, here you need right click the MBR disk, select “Convert to GPT Disk”.

Convert 4TB to GPT

Step2. It will pop out a window to ensure whether you want to convert MBR disk to GPT disk. Click OK, and you will back to the main interface.


Step3. Here you can see the disk 2 has already been marked as GPT. Click Apply to submit the operations, and wait till the progress finished.

4tb Apply

Finally, the disk has been converted, and you can partition the entire 4TB hard drive. However, if you would like to convert system disk from MBR to GPT like the Scenario, you can upgrade to AOMEI Partition Assistant Professional edition, which supports to convert boot disk between MBR and GPT without losing data. PS: if you want to convert boot disk from MBR to GPT style, you need to make sure that your computer supports UEFI mode, otherwise, the computer won’t boot successfully after converting.