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I have installed Ubuntu 18.04, but now I want to install Windows 10 (dual boot). At first, I have disabled CSM and then I made a partition using Ubuntu Live CD. Then I tried to install Windows but it showed an error saying the partition is not GPT format. So to make it GPT what should I do without loss of data in other partitions (i.e I have 4 partition- swap,ext4,efi and unallocated(ntfs))?
Thanks in advance.