How can I change mbr to gpt without data loss?

Safety checklist for converting an MBR Disk to GPT without data loss.

Create a Verified Backup

Make a full image of the disk.

Test-restore at least one file to confirm the backup isn’t corrupt.

Confirm Windows & Firmware Compatibility

Windows 10 version 1703 or later (or Windows 11) is required for mbr2gpt.exe.

Check that your motherboard supports UEFI boot (and know how to switch to it after conversion).

Check Disk Health First

Run chkdsk /scan or chkdsk /f to ensure no file-system errors.

Optionally run the drive maker’s SMART diagnostic—converting on a failing disk is risky.

Audit Your Partition Layout

1. Press Win + X → Disk Management (or use diskpart → list partition).
2. On mbr2gpt.exe targets: make sure there are ≤ 3 primary partitions and at least 100 MB of free space for the future EFI System Partition (ESP).
3. For GUI tools ensure the disk isn’t part of a dynamic-disk set or storage pool.

Suspend Write-Blocking Features

BitLocker: manage-bde -protectors -disable C: (resume after the reboot).

Any real-time antivirus or third-party disk-protection utilities should be paused temporarily.

By following the above rules, it will be more safe to change mbr to gpt without data loss on any Windows PC.