Post by drcard on Nov 17, 2021 22:48:30 GMT -5
Convert Hard Drive - MBR to GPT
Purpose:
Convert a MBR formatted hard drive to GPT format using a Windows built-in utility.
Overview:
Starting with Windows 11, the hard drive that Windows is installed on must be in the GPT format. The following instructions will show you how to find out what a drive’s current format is, how to test a drive to confirm that it can be converted, and how to perform the conversion without losing data.
Special Note:
These instructions apply to Windows 10 version 1703 and above, and attempts to convert MBR drives with earlier versions of Windows 10 will fail.
Quick Take:
Find Current Drive’s Format
* Open Disk Management
* Right click drive and select Properties
* Select Volumes tab
* Format listed as Partition Style
Test Drive for Conversion
* Open a Command Prompt with Administrative privileges and enter the following command
(replace _ with space):
mbr2gpt.exe_/validate_/allowfullos
* A response that “Validation successfully completed” means the drive can be converted.
Convert Drive to GPT
* In the Command Prompt with Administrative privileges, enter the following command
(replace _ with space):
mbr2gpt.exe_/convert_/allowfullos
* Upon completion of the conversion, reboot the system.
* Enter motherboard firmware to change the boot partition setting from Legacy
BIOS to UEFI mode so the new GPT drive can boot up.
Detailed Instructions:
The MBR (Master Boot Record) and the GPT (GUID Partition Table) are both NTFS styles of formatting. The difference is in the “logical address book” at the beginning of the drive. This address book keeps record where a file or folder is physically kept on the drive. The MBR uses 32 bit addresses and has only 232 possible addresses which only covers about 2.2 TBs of a hard drive addresses. The GPT uses 64 bit addresses and has 264 possible addresses which covers 9.44ZB (Zettabyte)(1 ZB = 1,024,000,000 TBs) of hard drive (which does not exist yet). GPT uses the UEFI boot mode which allows hardware security features to be used that MBR drives can’t use.
Windows 11 requires the storage structure of GPT and not MBR even on small drives because GPT is 64 bit and Windows 11 is 64 bit only, and Windows requires UEFI for security features. To prepare users for Windows 11, Microsoft created a tool to do the conversion and put this tool in a Windows 10 update. If you have updated to version 1703 or higher, then you should have the MBR2GPT.exe tool. Enter MBR2GPT.exe into the Start Menu search box and if you have it will show above the search box as a run command.
Before converting you need to see what format style the drive currently has. You may find that you don’t need to convert. If the drive is MBR style, you need to validate that the drive can be safely converted. After conversion, you will need to enter motherboard firmware (old timers called it BIOS). while the PC boots up and change the boot partition from Legacy BIOS to UEFI so the motherboard will mount the drive properly.
Find Partition Style of Drive
* Open Disk Management by pressing Win key + R to open a Run box and type diskmgmt.msc and press Enter key.
* Disk Management window will open and will take time to analyze all the drives before displaying them.
* In the lower pane, locate the Disk that has the Windows (C:) partition which is the Disk (drive) that Windows is installed on.
* Right click in this Disk block and select Properties. The Disk Properties window will be titled with the name of the drive.
* Select the Volumes tab.
* On the Volumes page, the entry for Partition style: indicates MBR or GPT.
* Many PCs that pass the Windows health check for Windows 11 upgrade will already be in GPT format.
* If the Disk (drive) is in GPT Partition style, no action is required.
Validate the Drive for Conversion
* Open a Command Prompt with Administrative privileges by pressing Win key + R to open a Run box, entering cmd, and pressing Ctrl + Shift + Enter keys. Yes to UAC authorization box.
* At the prompt (>) enter the following command, replacing the underscores (_) with a space, and press Enter key.
mbr2gpt.exe_/validate_/allowfullos
* It may take a while, but when validation is finished it will respond that the “validation failed” or “validation successful”. One reason the validation could fail is that the disk is already in GPT format.
Convert Drive to GPT
* Do not convert a drive from MBR to GPT unless it has a successful validation with the MBR2GPT tool.
* In the Command Prompt with Administrative privileges enter the following command, replacing the underscores(_) with a space, and pressing the Enter key.
mbr2gpt.exe_/convert_/allowfullos
* The conversion can take a while, depending upon many factors; so be patient. The utility will tell you when it is finished and that the “Conversion completed successfully”.
* Once the conversion is successfully finished you must reboot the PC and enter the start firmware of the PC (BIOS or UEFI). Exactly what key has to be pressed during the boot process to bring up the motherboard firmware differs with different manufacturers. Below is a list of common manufacturers of PCs and the key to press to enter the startup firmware:
Manufacturer’s Key to Startup Firmware
Manufacturer Key to Press
Dell/// F2 or F12
HP/// ESC or F10
Acer/// F2 or Delete
ASUS/// F2 or Delete
Lenovo/// F1 or F2
MSI/// Delete
Toshiba/// F2
Samsung/// F2
Surface/// Press & hold volume up button
* The startup firmware boot process has to be changed from Legacy BIOS for the MBR to the UEFI mode for the GPT formatted drive.
Comments:
* Conversion using the MBR2GPT tool preserves all the files and installed programs so Windows and programs should work as they did before the conversion.
* Any backup images of this Windows 10 on the MBR formatted drive cannot be restored to this GPT formatted drive without third party software. Non-image backups (does not contain the MBR address log) will restore to the GPT formatted drive.
********************************************************************************
The above tip is in a new format for better ease of use:
The Purpose is a quick one sentence reason to use the tip.
The Overview is a quick idea of what the tip contains and what it will do.
The Quick Take (aka: fast reading)is for experienced users who already know how to use the tools, but need the specific commands to do it.
The Detailed Instructions are written so a first timer can do it and there for those that need more detail on one step.
The original tip is written with screen captures in the Detailed Instructions to make following the instructions easier and less likely to go astray. This forum doesn't allow that much graphics in a posting, so I have to remove them when I post here.
This tip with screen captures (in PDF format) can be downloaded at the following link:
Convert Hard Drive - MBR to GPT
I would appreciate anyone viewing the original tip and giving me their comments on this format for tips.
Thank You,
Dana:>>
Purpose:
Convert a MBR formatted hard drive to GPT format using a Windows built-in utility.
Overview:
Starting with Windows 11, the hard drive that Windows is installed on must be in the GPT format. The following instructions will show you how to find out what a drive’s current format is, how to test a drive to confirm that it can be converted, and how to perform the conversion without losing data.
Special Note:
These instructions apply to Windows 10 version 1703 and above, and attempts to convert MBR drives with earlier versions of Windows 10 will fail.
Quick Take:
Find Current Drive’s Format
* Open Disk Management
* Right click drive and select Properties
* Select Volumes tab
* Format listed as Partition Style
Test Drive for Conversion
* Open a Command Prompt with Administrative privileges and enter the following command
(replace _ with space):
mbr2gpt.exe_/validate_/allowfullos
* A response that “Validation successfully completed” means the drive can be converted.
Convert Drive to GPT
* In the Command Prompt with Administrative privileges, enter the following command
(replace _ with space):
mbr2gpt.exe_/convert_/allowfullos
* Upon completion of the conversion, reboot the system.
* Enter motherboard firmware to change the boot partition setting from Legacy
BIOS to UEFI mode so the new GPT drive can boot up.
Detailed Instructions:
The MBR (Master Boot Record) and the GPT (GUID Partition Table) are both NTFS styles of formatting. The difference is in the “logical address book” at the beginning of the drive. This address book keeps record where a file or folder is physically kept on the drive. The MBR uses 32 bit addresses and has only 232 possible addresses which only covers about 2.2 TBs of a hard drive addresses. The GPT uses 64 bit addresses and has 264 possible addresses which covers 9.44ZB (Zettabyte)(1 ZB = 1,024,000,000 TBs) of hard drive (which does not exist yet). GPT uses the UEFI boot mode which allows hardware security features to be used that MBR drives can’t use.
Windows 11 requires the storage structure of GPT and not MBR even on small drives because GPT is 64 bit and Windows 11 is 64 bit only, and Windows requires UEFI for security features. To prepare users for Windows 11, Microsoft created a tool to do the conversion and put this tool in a Windows 10 update. If you have updated to version 1703 or higher, then you should have the MBR2GPT.exe tool. Enter MBR2GPT.exe into the Start Menu search box and if you have it will show above the search box as a run command.
Before converting you need to see what format style the drive currently has. You may find that you don’t need to convert. If the drive is MBR style, you need to validate that the drive can be safely converted. After conversion, you will need to enter motherboard firmware (old timers called it BIOS). while the PC boots up and change the boot partition from Legacy BIOS to UEFI so the motherboard will mount the drive properly.
Find Partition Style of Drive
* Open Disk Management by pressing Win key + R to open a Run box and type diskmgmt.msc and press Enter key.
* Disk Management window will open and will take time to analyze all the drives before displaying them.
* In the lower pane, locate the Disk that has the Windows (C:) partition which is the Disk (drive) that Windows is installed on.
* Right click in this Disk block and select Properties. The Disk Properties window will be titled with the name of the drive.
* Select the Volumes tab.
* On the Volumes page, the entry for Partition style: indicates MBR or GPT.
* Many PCs that pass the Windows health check for Windows 11 upgrade will already be in GPT format.
* If the Disk (drive) is in GPT Partition style, no action is required.
Validate the Drive for Conversion
* Open a Command Prompt with Administrative privileges by pressing Win key + R to open a Run box, entering cmd, and pressing Ctrl + Shift + Enter keys. Yes to UAC authorization box.
* At the prompt (>) enter the following command, replacing the underscores (_) with a space, and press Enter key.
mbr2gpt.exe_/validate_/allowfullos
* It may take a while, but when validation is finished it will respond that the “validation failed” or “validation successful”. One reason the validation could fail is that the disk is already in GPT format.
Convert Drive to GPT
* Do not convert a drive from MBR to GPT unless it has a successful validation with the MBR2GPT tool.
* In the Command Prompt with Administrative privileges enter the following command, replacing the underscores(_) with a space, and pressing the Enter key.
mbr2gpt.exe_/convert_/allowfullos
* The conversion can take a while, depending upon many factors; so be patient. The utility will tell you when it is finished and that the “Conversion completed successfully”.
* Once the conversion is successfully finished you must reboot the PC and enter the start firmware of the PC (BIOS or UEFI). Exactly what key has to be pressed during the boot process to bring up the motherboard firmware differs with different manufacturers. Below is a list of common manufacturers of PCs and the key to press to enter the startup firmware:
Manufacturer’s Key to Startup Firmware
Manufacturer Key to Press
Dell/// F2 or F12
HP/// ESC or F10
Acer/// F2 or Delete
ASUS/// F2 or Delete
Lenovo/// F1 or F2
MSI/// Delete
Toshiba/// F2
Samsung/// F2
Surface/// Press & hold volume up button
* The startup firmware boot process has to be changed from Legacy BIOS for the MBR to the UEFI mode for the GPT formatted drive.
Comments:
* Conversion using the MBR2GPT tool preserves all the files and installed programs so Windows and programs should work as they did before the conversion.
* Any backup images of this Windows 10 on the MBR formatted drive cannot be restored to this GPT formatted drive without third party software. Non-image backups (does not contain the MBR address log) will restore to the GPT formatted drive.
********************************************************************************
The above tip is in a new format for better ease of use:
The Purpose is a quick one sentence reason to use the tip.
The Overview is a quick idea of what the tip contains and what it will do.
The Quick Take (aka: fast reading)is for experienced users who already know how to use the tools, but need the specific commands to do it.
The Detailed Instructions are written so a first timer can do it and there for those that need more detail on one step.
The original tip is written with screen captures in the Detailed Instructions to make following the instructions easier and less likely to go astray. This forum doesn't allow that much graphics in a posting, so I have to remove them when I post here.
This tip with screen captures (in PDF format) can be downloaded at the following link:
Convert Hard Drive - MBR to GPT
I would appreciate anyone viewing the original tip and giving me their comments on this format for tips.
Thank You,
Dana:>>