If your MBR2GPT cannot find OS partition, this post may help you identify potential reasons and provide feasible fixes to address the issue. Besides, you can take some preventive measures to complete the disk conversion process smoothly and prevent data loss.
Are you facing the frustrating 'MBR2GPT cannot find OS partition' error while attempting to convert your disk from MBR to GPT? This error typically occurs when using the MBR2GPT tool to convert the disk layout on your computer. However, fear not! In this article, we will guide you through efficient methods and provide easy-to-follow tutorials to help you fix the 'MBR2GPT cannot find OS partition' error like an expert.
The 'MBR2GPT cannot find OS partition' error can occur due to various reasons, which include:
1️⃣Common disk errors:
2️⃣Incorrect disk specified:
Let's show how to check the disk number of my C drive in Disk Management. Please refer to these steps if needed.👇
3️⃣Partition number order issues:
4️⃣Incompatible boot mode:
5️⃣Incorrect partition flags: The operating system partition is either not formatted as NTFS or has incorrect attributes.
6️⃣Non-standard partition layouts:
7️⃣Run from WinPE or WinRE without proper mounting:
Since the MBR partition style is a major factor in this error, let's introduce two methods to convert MBR disks to GPT disks. You can choose either method based on your preference and level of expertise.
We highly recommend EaseUS Partition Master if you're a Windows user looking for a reliable, user-friendly program to convert your disk from MBR to GPT. Its partition-style conversion feature lets you change the partition style of your target disk without losing data.
Pros and Cons of EaseUS Partition Master:
👍Pros:
👎Cons
❓Why we recommend EaseUS Partition Master:
It is a good tool for viewing and managing partitions on all your hard disks, and with support for larger disks, the tool becomes even better. You might want to give it a try the next time you wish to change something on your hard disk. - from The Windows Club
EaseUS Partition Master is a fantastic choice due to its simplicity and effectiveness. It eliminates the complexities often associated with disk conversion, making it an ideal solution for users who prefer a straightforward approach. - from the Editor
Step 1. Install and launch EaseUS Partition Master on your computer.
Step 2. Open the Disk Converter tab, select "MBR => GPT" and click "Next" to continue.
Step 3. Choose the target MBR disk, and click "Convert" to start the conversion.
Feel free to share this method to help more of your friends who are looking for an efficient solution in switching a disk from MBR to GPT without losing any data online:
The MBR2GPT.EXE provides a straightforward method to convert your MBR disk to GPT for those experienced with command-line operations and Windows 10 version 1703 or later. It's important to consider both the benefits and the drawbacks of using this command-line tool.
Pros and Cons of MBR2GPT command lines
👍Pros:
👎Cons
Steps to Convert MBR to GPT with MBR2GPT Command Lines
If your Windows requirements match and you are comfortable with command-line interpretation, you can follow the steps below.
But before that, you're recommended to check the disk number of the target MBR drive you want to convert.
▶️Please press Windows + X > choose Disk Management to open the Windows Advanced Storage tool > right-click on your targeted MBR disk > select Properties > under the Volumes tab, locate the disk number. For instance, in the following picture, the disk number of this MBR drive is "0".
Then you're ready to follow the steps below.
Step 1. Open Command Prompt as an administrator:
Step 2. Validate the disk: In the Command Prompt window, type mbr2gpt /validate /disk:0 /allowFullOS.
Step 3. Convert the disk: In the Command Prompt window, type mbr2gpt /convert/disk:0 /allowFullOS.
There can be multiple reasons behind the 'MBR2GPT cannot find OS partition' error during the disk conversion process. To resolve this issue, follow the methods outlined below.
Here, you need to change your computer's boot mode from Legacy to UEFI, as only GPT supports UEFI, MBR only supports BIOS/Legacy. Follow these steps:
Step 1. Restart your computer.
Step 2. Keep pressing the corresponding key, such as F2, F12, Del, or Esc, to enter BIOS. It's mainly up to the manufacturer of your computer.
Step 3. Navigate to the Boot, Boot Mode, Boot Order, or Boot Sequence setting > change BIOS mode from Legacy to UEFI.
Step 4. Disable Legacy Support or Legacy Boot if some systems have this option separately.
Step 5. Please save these changes > exit it.
Solved: MBR2GPT Cannot Find Room for the EFI System Partition
If you encountered the MBR2GPT cannot find room for the EFI system partition error, you can follow this comprehensive tutorial to fix it.
The SFC/Scannow command scans for and fixes damaged or missing Windows system files, helping the operating system work properly. Let's show how it works.
Step 1. Type cmd in the search bar > select Run as administrator or press Win + X > choose Windows PowerShell (Admin) > to open the Command Prompt window.
Step 2. In the Command Prompt window, type DISM.exe /Online /Cleanup-image /Restorehealth.
Step 3. After DISM completes, type sfc /scannow > press Enter.
Step 4. After scanning and repairing, type exit > press Enter.
If this method helps you fix this error, share it to help more people with the "MBR2GPT cannot find the OS partition" issue online:
It's important to ensure the target disk is in a good state before converting. Follow these steps:
Before starting the disk conversion, ensure the target disk is in good condition. Take these actions to check it:
Step 1. Right-click the Start button > choose Disk Management to open it.
Step 2. Verify that the destination disk is present in Disk Management and that a drive letter has been allocated.
Step 3. To ensure the disk can be accessed without any problems, try opening it.
You can proceed to the next step and successfully complete the disk conversion if the disk is sound and operating normally.
To prevent encountering the 'MBR2GPT cannot find OS partition' error, consider implementing the following tips:
By following these practical tips, you can reduce the likelihood of encountering the 'MBR2GPT cannot find OS partition' error and ensure a smoother disk conversion.
In conclusion, if you encounter the 'MBR2GPT cannot find OS partition' error, avoid using the MBR2GPT command and instead follow the methods outlined in this article to resolve the issue efficiently.
Meanwhile, remember to take preventive measures, such as setting the compatible boot mode, promptly fixing system file errors, maintaining disk health, and backing up data. By following these guidelines, you can overcome the error and complete the disk conversion process smoothly.
Here are a few questions that might help you address and find solutions to fix MBR2GPT if it is unable to find the OS partition error:
1. Can I convert non-OS disk with MBR2GPT?
No, the MBR2GPT utility only converts the disk containing the operating system (OS) from MBR to GPT. It cannot be used to convert non-OS disks.
2. What to do if MBR2GPT reports disk layout validation failed?
If MBR2GPT reports a "disk layout validation failed" error, ensure the disk meets conversion requirements and is not locked or in use. Run disk error-checking tools like chkdsk and consider backing up data before initializing the disk as GPT or performing a clean OS installation if necessary.
3. What is the best MBR2GPT alternative software?
One of the best MBR2GPT alternatives is EaseUS Partition Master. It offers a user-friendly interface and a "Convert to GPT" feature for seamless disk conversion.
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