Can't Add Partition to MBR disk Using Unallocated Space on Windows Server, I Need Help

Guys, can I add this unallocated space to my MBR disk? My disk has over 2TB of space, but the remaining 400GB is shown as unallocated space. I can't use this unallocated space in Disk Management or add her to the C partition. Disk management tells me that on the MBR disk, there is only 2TB usable. What should I do to add the unallocated space to the C drive and make it available?

Best Answered by

Sherly· Answered on Dec 20, 2023

Hello, the first thing you need to know is that MBR and GPT are two popular partition styles on Windows and Windows Server. They are the standard for the layout of storage devices such as HDD or SSD. The partition style tells Windows how to access data on the current disk and is determined during disk initialization.

But there is a big difference between the two; one of the important differences is that the partition size of MBR disk is limited to 2TB. That is to say, on MBR, space over 2TB is not available. If you want to break this limitation, you need to convert the entire disk from MBR to GPT. 

You can directly convert MBR to GPT via Disk Management. However, if your disk contains OS or important data, you would rather not use Disk Management since it can't convert a disk with the operating system, and it will cause data loss.

Hence, we recommend you choose EaseUS Partition Master Server; this tool won't cause any data loss during the conversion. Here is how you can convert MBR to GPT via EaseUS Partition Master Server:

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Step 1. Download and run EaseUS Partition Master.

Step 2. Click the "Disk Converter" option to choose the target MBR disk.

Step 3. Click "Start" to begin to convert.

After the steps above, you can see all the disk space. Hope my answer can help.

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