Quite often, users are faced with a problem that they think is big when they need to convert a partition style from GPT to MBR. This may be due to many factors, among which the main one is the impossibility of installing some OS in such sections and compatibility with the new standard of the primary input / output system UEFI, which replaced the BIOS. There are several ways to convert sections with more modern GPT markup to MBR and vice versa. But you can replace one style with another with or without data storage. Consider each such option, since some actions may come in handy even when you first or reinstall the operating system on your computer.
The difference between the GPT and MBR styles
To begin, let's see what, in fact, is the difference between such styles, and for what each of them can be used. The MBR markup (with boot record) is believed to be outdated today, and it has been replaced by a new GPT style. Partitioning of this type on the hard drive is mandatory if the hard drive has a volume of 2 TB or more. But to ensure the correct operation with such partitions and use their full volume, the necessary updated version of the primary system, designated as UEFI.
In the case of using MBR and BIOS, installing disks of such a volume on modern computers becomes simply meaningless, since the BIOS does not support them, and when the UEFI mode is disabled, despite the definition of the media in the primary system, the full disk space will be unavailable. So, think a hundred times to what extent the implementation of the actions described below is appropriate.
Problems with operating systems
But the main problem is that outdated operating systems like Windows 7, which are still popular among many users, are not installed in partitions with GPT markup, and even do not support the main UEFI mode of operation. For the installation, some users suggest disabling UEFI to use Legacy mode, as for a regular BIOS. On the other hand, if you purchase a new computer with the primary UEFI system already installed instead of the BIOS, the G8 will not install when UEFI is disabled. Thus, we obtain two mutually exclusive factors. However, you can get around such obstacles using fairly simple methods, but you will have to work a little.
Converting on Windows installation
First, let's focus on how to convert GPT to MBR when installing Windows or vice versa. In this case, the safety of data on the disk is not guaranteed, since it will have to be formatted during the installation of the operating system. Despite the fact that these questions are only indirectly related to the main topic, it will not hurt to have knowledge on them.
At one of the stages after the start of the installation process, the installer of the same “seven” displays a message stating that installation into the selected partition is not possible. In this case, the simplest solution is to delete all partitions on the disk and install Windows in the unallocated area.
You can also create a system partition for Windows yourself, and use the rest of the space for logical volumes. However, this will not automatically create a special reserved partition, which will affect the fault tolerance of the installed OS. The installation section will be automatically converted to the desired style.
Thus, if we are talking about how to change the GPT to MBR, you need to use the command line tools (Shift + F10), which prescribes the following commands shown in the image above. After that, you can continue to install the system in normal mode.
How to change GPT to MBR: create a bootable flash drive and select the start mode of the primary input / output system
Now let's go back to the starting point and decide on the actions that may be required to convert styles from an already installed OS (for example, Windows 8/1). To do this, you will initially need to create a bootable USB flash drive with the Hard Disk Manager version 15 program from Paragon or a similar utility from Acronis (Disk Director). The media itself is elementarily created in a small Rufus application, and then set first among boot devices.
Immediately in the settings of the primary system, you must immediately change the Boot Mode from UEFI to Legacy and disable Secure Start. Such actions are needed only if you created a regular bootable USB flash drive for MBR, and not EFI.
Partition Conversion Process
Now you need to boot from the created media. The essence of how to change the GPT style to MBR is to delete all sections in the program at the first stage, including those reserved by the system for recovery, leaving only the one on which the installed OS is located.
When deleting backup partitions in the confirmation window, it is necessary to check the box next to the refusal to request volume label next time. At the end of these steps, only the base GPT partition will remain. How to remake GPT in MBR at this stage?
To do this, through the PCM in the additional menu, select the appropriate conversion item and confirm your actions. Since the operation will be transferred to the deferred category (as well as in other utilities like Acronis Disk Director), you need to click the "Apply" button, and then the conversion process will start.
Additional steps to create a backup partition
But that is not all. The fact is that after changing the style, the system just won’t boot, and besides, you need to create a backup section for it with the boot data of the installed OS with the volume of about 300 MB. This can be done through the PCM menu on the unallocated area with the choice of the partition creation point, after which you will need to specify its size and file system (NTFS), and after completing operations through the same menu, make the partition active.
Creating a configuration to boot an installed system
At the final stage, it remains to create a configuration that the same "eight" could boot with the new partition style without problems. In this case, you need to restart the computer, boot from the installation media and call the command console. In it, you need to determine which letter is assigned to the active boot partition. To do this, first enter the diskpart command, and then lis dis, which displays all active partitions.
We remember the letter of the disk on which the system is installed, we execute the command to exit the main tool exit, and after it we enter the line bcdboot N: \ Windows, where N is the letter of the system partition. After that, we reboot the computer again, but in normal mode, setting the UEFI to a normal load, and rejoice. You can check the changed style directly through the section properties on the volume tab.
Windows Tools
In principle, speaking of how to change GPT to MBR, one of the solutions for working OSes is to offer their own tool in the form of disk management tools (diskmgmt.msc).
Here you can also delete unnecessary sections, and then select the conversion from one style to another through the RMB menu on an unallocated space. True, the only and main limitation is that such actions can only be performed for non-system disks or logical partitions, that is, it will be impossible to change the style of a Windows disk directly in the system.
Changing the style of a section using third-party programs
And finally, a few more words about how to change GPT to MBR. As more convenient tools than those available in Windows, you can use special disk programs from Acronis, AOMEI, Paragon and other developers. The operations performed, in general, do not differ much from those just described for Windows tools and are reduced to converting unallocated space into the selected style. However, the conversion is much faster and more efficient. The interface of such programs is very similar to the Windows disk management section, but some operations (for example, reallocation of disk space) are made much easier by using the most common fader (slider), by moving which you can select the required sizes for each partition.
Brief Summary
Here's a quick summary of everything about style conversion. As it is already clear, if we are talking about the implementation of transformations with the preservation of a workable system and data that may be located in the system partition, you only need to use disk utilities with the preliminary creation of bootable media. If the storage of information is not required, you can convert it at the stage of reinstalling the OS, and using Windows, and using third-party programs. But changing the main section in a working system will not work even with their help, no matter how you like it. It will be impossible to remove it!