How to convert MBR partition table to GPT?

Question

I need to install Windows 10 alongside of Ubuntu, but partition table type is MBR, I tried to turn off UEFI mode, use legacy-mode but Windows still don't wont to be installed. (I heard of gdisk utility but didn't understood how to use it) And how to restore grub after this ?

Answer 1

Use the built-in windows tool MBR2GPT. You should be able to use it if you use latest windows. Backup any data in File Systems like ext4 or btrfs which are not recognised by windows as it might cause data loss. Before using it, you should read the requirements of your HDD or SSD for a successful conversion.

Answer 2

If you have windows installed, you can use AOMEI Partition Assistant to convert your partition table from MBR to GPT , or from GPT to MBR. download it here http://www.disk-partition.com/free-partition-manager.html

To install Ubuntu alongside windows 10, do following - Valid for both GPT & MBR partition:

1)Make a partition at least 20GB & do not format it. just keep it Unallocated, in case you format it , delete it.(just like the black partition which is unallocated)

2)Reboot and boot from your installation disk/USB, when it asks for Installation type, Select the 1st option . i.e

• Install Ubuntu alongside Windows Boot Manager

(the image below was copied from google image search)

3)You don't need to configure any kind of parition here , setup will automatically do this for you.

4) Finally Install GRUB Boot-loader to you Hard disk and you are done.now when you boot your machine, you will see boot options to choose from. if you don't see such options, go to Boot Devices in your BIOS ( Press F9 or F12 ) and select

• Ubuntu

or

• UEFI- Ubuntu

EDIT : As commented by Zacharee1, you don't always have to format entire hard drive, you can be smart. just use AOMEI Partition Assistant. it convert MBR to GPT without data Loss.

If you face any issue, comment back.

Hope it helps!