There are different ways partition tables are stored on a drive. The most widely used methods are MBR (Master Boot Record) and GPT (GUID Partition Table). Modern or newer versions of Windows and other operating systems can use the old Master Boot Record (MBR) or the newer GUID Partition Table (GPT) for their partitioning scheme. GPT is more advanced and more required to boot Windows systems in UEFI (Unified Extensible Firmware Interface) mode. MBR is required to boot older Windows systems in BIOS mode. For more information on MBR and GPT, you can check out our post - MBR VS GPT.
How to determine which partition table the disk uses
There are two ways to check which partition table the disk is using −
by using the command line
By using Windows' graphical disk management tool.
#1. Using the Diskpart command
You can examine the partition table using standard DiskPart commands in a Command Prompt window. First, you need to run the Command Prompt window as administrator by right-clicking the Start button or pressing Windows key + X and selecting "Command Prompt (Admin)". You can also go to the Command Prompt shortcut in the Start menu, right-click it, and select "Run as administrator".
Type the following two commands, pressing Enter after each completion:
DISKPART
disk list
You'll see a table listing the disks. If the disk is GPT, there will be an asterisk (* character) under the "GPT" column. If it's an MBR disk, this will be blank under the GPT column.
For example, in the screenshot below, disk 0 is a GPT disk.
#2. Use Disk Management Tools
Another way to identify the partition table is to use the Disk Management tool that comes with Windows. To access it, right-click the Start menu or press Windows key + X, then select Disk Management. You can also press Windows key + R to open the Run dialog, type "diskmgmt.msc" into the restricted area, and press Enter.
Now, find the disk whose partition table you want to check in the Disk Management window. Right click on it and select Properties.
Click on the "Volumes" tab. To the "Partitioned" right, you will see either "Master Boot Record (MBR)" or "GUID Partition Table (GPT)", depending on which disk is used.
How to Convert Between MBR and GPT
To convert a disk from MBR to GPT, or from GPT to MBR, you must clear the disk's data first. Therefore, back up any data on the disk whose contents were previously wiped. The conversion method explained below shows how to wipe the disk of all contents and partition tables, then convert it to another partition scheme and set it up again from scratch.
There is also another way to convert between disks. Some third-party partition management programs guarantee that they can convert MBR to GPT and GPT to MBR without any data loss. However, Microsoft does not officially support them before running such programs in case, therefore you will have to back up your data anyway you face technical issues which lead to data loss.
Therefore, it is safer to just backup the drive, wipe the data, convert the partition scheme, and move any necessary data back to the disk. It may Latest Mailing Database take more time than using the convert function, but this is the officially supported way you have, and you won't run into any issues, partitions or data loss is inevitable. Here you can do the conversion by using Command Prompt or Disk Management tool.