The "Windows Cannot Be Installed to This Disk MBR" error is generated due to incompatibility between EFI and MBR partition tables. Fortunately, this problem can be easily fixed. In this post I will explain everything you need to know to deeply understand the origin of this problem and I will also show you how to fix it without losing the information on the MBR partition.
"Windows Cannot Be Installed to This Disk MBR" is an error that occurs when trying to install 64-bit versions of Windows 7, 8 or 10 on a disk that has been previously configured to use an MBR partition table. This is a compatibility error but fortunately it is easy to solve.
To understand what a partition table is, it is important to know how a hard drive works. Hard drives are made up of several platters made of polished glass, ceramic or aluminum compounds and coated on both sides with a very thin layer of a metal alloy mounted on a central axis with a head that emits and interprets magnetic signals. This means that the information stored on the disk is shaped by the binary interpretation of the magnetic charge on the surface of the thin metallic layer of the platters, which is organized by tracks and sectors. The data read and write capacity of a hard disk depends on two factors, the revolutions per minute (RPM) that the hard disk drive can perform and the information management by sectors.
Now you know what the physical limitations of a hard drive are and even though a hard drive can read and write millions of bits per second, it does not mean that the information is physically arranged in the most efficient way possible. For this reason, it is necessary to establish a logical order in the physical sectors of the disk.
Partitions, as the name implies, are logical segmentations of a disk whose function is to separate the information sectors and organize them in a practical order. This creates a virtual volume that the operating system will interpret and treat as a separate volume. It is for this reason that partitions are usually used to separate and protect the operating system.
Partitions play a very important role, but they would be useless without software support. The Firmware, either BIOS or UEFI and the operating system are in charge of managing these partitions and information sectors through a data structuring system called partition table.
MBR (Master Boot Record) is a sector structuring scheme. This type of structuring was developed based on the guidelines and limitations of BIOS in 1983, since at that time it was the most efficient and reliable method of managing the data necessary to start an operating system and load it into RAM memory, however, over time and due to the constant evolution of the hardware industry, it was necessary to develop a partition table that was more efficient and secure. This is why in 2005 the sector structuring type (GUID) GPT was implemented. This partition table far exceeded the limitations of the MBR partition table and brought considerable improvements over data management but was developed based on EFI's capabilities and limitations.
The MBR partition table is not bad but it was designed for a different time. MBR was designed to work with 32 bit data architectures, therefore, it was impossible for it to manage disks larger than 2TB nor more than 4 partitions per disk, and on the other hand, GPT was designed to work with 64 bit data architectures, which allows the management of disks up to 9.4 ZB and can manage up to 128 partitions.
To understand what EFI is, it is important to know what the Firmware of your computer is. In electronics and computing, firmware is software that manages hardware at the most basic level possible. In computing, firmware must be able to manage and synchronize the operation of several components at once. It is very common for a computer to be made up of pieces of different brands, so it is necessary for a motherboard to be able to control different measurements of voltage, frequency or temperatures. This is why in 1975 the Basic Input / Output System (BIOS) was introduced. This software had to be light enough to be stored on a non-volatile ROM on the motherboard and at the same time had to be able to allow the user to edit the operating parameters of the installed hardware.
BIOS, without a doubt, was a great technological advance that allowed the evolution of the computer industry; however, this software was designed more than 40 years ago, with a 16-bit architecture and an interface that looks increasingly outdated.
EFI (Extensible Firmware Interface) was designed to overcome BIOS limitations. EFI is capable of working with 32 and 64 bit architectures, which represents an immense improvement regarding compatibility and this at the same time allowed the use of a much more practical and intuitive graphical interface.
As I mentioned before, MBR is a data structuring scheme designed to work together with BIOS, while GPT was developed based on the limitations of EFI, for this reason, it is important to know if your computer uses EFI or BIOS to properly choose the partition table that you will use.
There are two easy methods to fix the error "Windows Cannot Be Installed to This Disk MBR". Below I will talk about them.
Boot from a Windows Installation Media and press the Shift + F10 keys, this command will execute Command Prompt in administrator mode, there you must enter the following codes in the order that I will show below. (don't forget to press "Enter" after typing each code).
The previous method is foolproof but losing the data can be unfeasible in some cases. On the other hand, UEFI offers the option to exchange the boot software between Legacy (BIOS) and UEFI, in this way you could force the compatibility with the operating system.
During the startup of your computer, press the F1 / F2 / F8 / F10 key (the key will depend on the motherboard manufacturer) Now you must go to the "Boot" section and set the parameter of "Legacy Boot Option Priority" to "Legacy.”
Restore your data
As you may have noticed, if you use method 1, you will successfully install the operating system but you will have removed all the content that was in that partition, on the other hand, if you use method 2 you can install Windows but the partition will continue to use the MBR partition table, which may eventually cause problems due to its limitations. I personally recommend opting for method 1 to be able to enjoy the privileges offered by the GPT partition table and then use professional data recovery software like Recoverit. Below I will show you how easy it is to recover deleted or corrupted information from disk through Recoverit. You can download the software for free through its official website. https://recoverit.wondershare.com/. Below I will show you how to use it.
Step 1: Choose a drive to scan
Once you’ve installed and opened the software, select the drive where the deleted data was located
Step 2: Select the files to recover/restore
Now all you have to do is select the folder or folders you want to recover/restore and click on “Recover”.
MBR partition tables were for a long time the best option regarding structuring information sectors on disks, however, over time the technology has evolved exponentially, and it is for this reason that it was necessary to develop a data structuring system more efficient. Changing the partition table of your disk to GPT is a wise decision and with the help of Recoverit, you can perform this conversion without losing your data in a very simple way.