Can I convert mbr to gpt during Windows installation without data loss

If you are converting MBR to GPT using Microsoft's mbr2gpt tool, after you convert MBR to GPT, your PC has to boot in UEFI mode. If it’s stuck in legacy BIOS mode, you’re gonna hit some roadblocks. You’ll need to change the boot settings in the firmware, which can get a little tricky if you’re not familiar with it. If you’re using certain features like BitLocker encryption, you might need to take extra steps to handle that. Sometimes, it can get wonky during the conversion, so you might have to decrypt first or deal with other hassles.

Not every old BIOS system can handle UEFI well. If you’re trying this on a really old machine, be ready for some compatibility headaches. You might end up stuck if the hardware doesn't support UEFI properly. While mbr2gpt is a Microsoft tool, it’s still relatively new and might not cover every edge case. So, if you have a custom setup or some unique partition scheme, you might be playing with fire.