How to Convert Legacy Bios to UEFI in Windows 10

Why Convert Legacy BIOS to UEFI?

Converting Legacy BIOS to UEFI can significantly enhance your system's performance and security, particularly if you are planning to upgrade to the latest versions of Windows. UEFI offers faster boot times, support for Secure Boot, and the ability to handle larger disk sizes compared to Legacy BIOS.

Prerequisites for Conversion

Before you begin the conversion process, ensure your system meets the necessary prerequisites to avoid any potential issues.

UEFI Support: Verify that your motherboard supports UEFI firmware. Generally, motherboards released after 2014 support UEFI secure boot, but it's crucial to check your specific device. You can do this by pressing Win + R, typing msinfo32, and checking the BIOS Version/Date in the System Information window. If it says UEFI, your device is eligible.
Windows Version: Ensure you are using Windows 10 version 1703 or higher. You can check this by pressing Win + R, typing winver, and looking for "version 1703" or higher on the second line.
64-Bit Processor: UEFI BIOS is only supported by 64-bit processors, so make sure your system has a 64-bit architecture.
Disk Partitions: The disk you are converting should have no more than three partitions. If your disk has more than three partitions, you will need to combine or erase the extra partitions to avoid a "Disk Layout Validation Failed" error.
BitLocker: If your system is encrypted with BitLocker, decrypt the disk and disable BitLocker protection before starting the conversion process.

Backing Up Your System

Although the conversion process does not result in data loss, it is highly recommended to back up your system as a precaution. This ensures that your data is safe in case any unexpected issues arise during the conversion.

Steps to Convert Legacy BIOS to UEFI

Stage 1: Convert MBR to GPT

To convert from Legacy BIOS to UEFI, you need to convert your system disk from MBR (Master Boot Record) to GPT (GUID Partition Table).

Using MBR2GPT Tool

Access Command Prompt: Restart your system while holding the Shift key to enter the Advanced Startup screen. Go to "Troubleshoot -> Advanced Options" and select "Command Prompt".
Validate the Disk: Type the following command and press Enter:
```
mbr2gpt /validate
```
If you see the "Validation completed successfully" message, proceed to the next step. If you encounter errors, use the following command to validate with full OS support:
```
mbr2gpt /validate /allowFullOS
```
Convert the Disk: Execute the following command to start the conversion process:
```
mbr2gpt /convert
```
Restart and Verify: Restart your system and verify the conversion by opening Disk Management (diskmgmt.msc) and checking if the partition style has changed to GPT.

Using MiniTool Partition Wizard

Launch MiniTool Partition Wizard: Download and launch MiniTool Partition Wizard.
Convert MBR to GPT: Right-click the system disk and choose the "Convert MBR Disk to GPT Disk" option. Read the warning information and click "OK".
Apply Changes: Click the "Apply" button to execute the pending operation.

Stage 2: Change BIOS Mode to UEFI

Enter BIOS Settings: Restart your computer and enter the BIOS settings by pressing the specific key for your motherboard (usually Del for desktops and F2 for laptops).
Disable Legacy and Enable UEFI: Under the Boot tab, disable Legacy and enable UEFI.
Save and Exit: Press F10 to save the settings and exit the BIOS settings screen.

Post-Conversion Verification

After converting your system disk to GPT and changing the BIOS mode to UEFI, verify that the conversion was successful:

Check Disk Properties: Open Disk Management (diskmgmt.msc) and go to the "Volumes" tab. You should see "GUID Partition Table (GPT)" next to "Partition style".
System Information: Open the System Information tool (msinfo32) and check the BIOS Mode, which should now display UEFI.

By following these steps carefully, you can successfully convert your Legacy BIOS to UEFI without reinstalling Windows, ensuring your system is compatible with the latest versions of Windows and leveraging the enhanced features of UEFI.