Diskpart Is showing One Partition as Two Different Ones, How Can I Do?

I want to convert my hard disk from MBR to GPT via mbr2gpt. Still, for it to work, I can have a maximum of three primary partitions and diskpart labels in the same partition as two separate partitions. While I only have four partitions, the diskpart shows five. However, Disk Management shows only four partitions. How can I fix this?

According to your description, there is a partition that has two different drive letters in the Diskpart. This is probably because you forget to delete the partition when you create the logical partition. Then why Diskpart shows five partitions while Disk Management only shows four? The reason is Disk Management will hide one of the drive letters if they are the same partition. 

Delete the extended partition

Before converting the disk from MBR to GPT, you need to delete the extended partition first. Don't forget to back up your valuable data on the partition. The steps for deleting the partition are as follows:

Open "Disk Management" > Right-click the extended partition > choose "Delete Volume" > select "Yes."

I believe your disk returned to normal now. If you want to convert your hard disk from MBR to GPT via Diskpart, continue to read and learn the whole conversion process.

Convert MBR to GPT via a third-party tool

Using Diskpart to convert could be troublesome since it will erase all your data on the disk. It is recommended to convert MBR to GPT with a professional disk converter. Based on my experience, EaseUS Partition Master can easily meet all your demand for converting partition styles. This tool allows you quickly realize the conversion between MBR and GPT without data loss.

The specific steps for converting MBR to GPT using EaseUS Partition Master are as follows:

Note: A full backup in advance is the best recovery solution for unexpected data loss.

Enable the UEFI boot mode

After the conversion process, you need to set up the UEFI boot mode to boot from the new GPT system disk. You will learn how to enable the UEFI boot mode from the below link:

Further Reading: How to Enable UEFI Mode?