About Disk Management

Disk Management is a built-in tool in Windows which enables you to create/delete/format/shrink/extend partition. A lot of PC users choose to create partition with Disk Management, but sometimes many users realize there is no option to create a new partition in Windows 8 or 7. They confused by this problem and try again and again, but the result is the same.Why does this happen?

Why No Option to Create a New Partition in Windows Disk Management Tool

Maybe the reason why there is no option to create a new partition in Windows Disk Management is different. But we will show you the common reason as follows:


With Disk Management, you can only create a new partition within unallocated space not existing partition. So there may come out a situation that is the users making new partition with existing partition rather than unallocated space.

If you make this mistake, just click unallocated space and then choose Create New Volume. However, if there is no unallocated space in your disk, you should shrink partition to get unallocated space at first.


Another reason you can’t create a new partition is caused by disk type. For example, you have a MBR disk which is 3 TB, you only use about 2TB space, however when you need to create a new partition with another 1TB free space in Windows Disk Management, you will find you aren’t allowed to do this.

The issue is due to the differences between MBR and GPT. The maximum of storage space supports by MBR is 2TB, which means even you have a 3TB MBR disk, you can only use 2TB, the rest of 1TB can’t be used to create new partition.

Fortunately, the third-party software –AOMEI Partition Assistant Professional can help you solve the problem. Due to this partition management software allows you to convert MBR to GPT. And GPT can support hard disk whose size is larger than 2TB. After this conversion, you can create a new partition.

Convert MBR Disk to GPT with AOMEI Partition Assistant Professional

 It is well acknowledge that if you want to convert MBR disk to GPT with Disk Management in Windows 8 or 7, you should delete all the data on the disk and then you can make the conversion. Actually it is not a reasonable method for you. However, with AOMEI Partition Assistant Professional, you can convert to GPT without data loss.

Before you do:

If you want to convert system disk from MBR to GPT, please make sure your motherboard supports UEFI

Step1: Download, install and launch the software. Right click the disk you want to covert and then select Convert to GPT Disk.


Step2: Click OK to continue the operation.


Step3: You can preview the conversion, to operate the change, please click Apply.


After you converting MBR to GPT, you can directly use AOMEI Partition Assistant Pro to create a new partition even there is no unallocated space. In this way, you don’t need to worry no option to create a new partition in Windows Disk Management tool. Besides, this powerful software is able to allocate free space, convert dynamic disk to basic, make bootable CD and more.