Solved: Convert to GPT Greyed Out in Server 2012

Find that Convert to GPT Disk greyed out Server 2012 in Disk Management? Don’t worry, this post shows why it occurs and how to solve it in an easy way.


By Emily / Updated on May 12, 2023

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Convert to GPT greyed out in Server 2012

To solve issues like 4TB hard drive showing only 2TB, can’t create more primary partitions in Windows Server 2012, you may choose to convert disk into GPT. However, after accessing Disk Management and right click the MBR disk, you may find that the option of Convert to GPT Disk is greyed out.

Convert To Gpt Greyed Out Server

Why can't convert to GPT on Server 2012?

Disk Management in Windows Server 2012 offers you function to convert disk into GPT. However, it only supports convert empty basic disk into GPT. When the MBR disk holds partition(s), the options of Convert to GPT Disk will be disabled and you cannot make conversion for this disk.

How to solve unable to GPT Server 2012?

Having realized why can’t convert disk to GPT in Windows Server 2012 Disk Management, you know that deleting all partitions on the disk will be an effective solution. In fact, this way is helpful for data disk. However, deleting system partition within Disk Management is not allowed. That is to say, you can’t convert system disk into GPT within Disk Management as you are unable to remove all partitions on it. At this point, it is very necessary to turn to a reliable third party MBR & GPT conversion tool.

For detailed steps to delete partitions and convert or convert MBR to GPT without data loss in Windows Server 2012 via third party tool, refer to the following context.

Solution 1. Delete all partitions and then convert within Disk Management

To apply this way, what you should confirm and prepare:

  • The MBR disk that you want to convert doesn’t have Windows Server 2012 operating system installed.

  • As deleing partition will erase all data on the partition, you should back up the MBR disk or necessary files on it in advance.

Then, do as the following steps.

Step 1. Enter Disk Management, right click on each partition on the disk that will be converted to GPT and choose Delete Volume to make the disk unallocated.

Delete Volume Server

Step 2. After all partitions are removed, you can see that the disk shows as an unallocated space in Windows Server 2012 Disk Management. Now, you can right click the MBR disk and choose Convert to GPT Disk.

Convert To Gpt Clickable Server

Step 3. Follow the prompt to complete MBR to GPT conversion.

If there are multiple parttions on your MBR disk, you can choose to delete all partitions at one time and then conver to GPT via Diskpart utility. Syntax would be: list disk > select disk n > clean > convert gpt

Solution 2. Convert disk to GPT without data loss via third-party software

When your MRB disk holds OS or you want to make conversion easier, you can turn to a trusted and powerful MRR & GPT conversion tool, AOMEI Partition Assistant Server. With it, you can convert system or data disk from MBR to GPT disk in Server 2012 directly and simply. Designed with modern and user-friendly interface, it is easy to use even for newbie. And it can also work with Windows Server 2022/2019/ 2016/ 2012 R2/2008 (R2) and etc. Now, have a closer look at how it works.

Download DemoWin Server & PC
Secure Download

Step 1. Install and run this software. Right click the disk that going to be converted and choose Convert to GPT.

Convert Data Disk To Gpt

Step 2. Confirm this operation and click OK.

Ok To Gpt Data Disk

Step 3. Click Apply and Proceed to commit your operation.

Apply To Gpt Data Disk

★ Don’t abnormally terminate the program during the conversion to ensure the data is consistent.
★ For converting MBR system disk into GPT in Windows Server 2012, ensure that your motherboard support UEFI/EFI before conversion and change boot mode to UEFI/EFI after the operation.
★ AOMEI Partition Assistant Server enjoys many other functions, such as cloning the disk, migrating OS to SSD, and so on.


Now, you may have known how to solve the "Convert to GPT greyed out server 2012" problem. From what we have talked about, AOMEI Partition Assistant Server can help a lot in fixing this issue. Get this great software now and have a trial.

Emily · Staff Editor
Emily is an English editor of AOMEI Technology; she has a great passion for providing easy solutions for people to tackle with all disk or partition management problems. In addition to writing articles about disk/partition management, she also edits great tutorials on how to back up and restore disk for data security. In her spare time, she loves to learn computer skill to improve herself or stay with her family to enjoy a good day.