I put in a WD 1TB Hard Drive and gave myself a 200 GB partition and I tried to load Windows 10 on the 200 GB partition because the other 800 GB has my data and this is the message I got.
"Windows cannot be installed on this disk. The selected disk has an MBR partition table. On EFI system, Windows can only be installed to GPT disk".
I Convert my entire disk over to GPT then made a 200 GB partition and format. I loaded Windows 10 and it gave me a choice of Drive 0 Partition 1 128MB and Drive 0 Partition 2 195.3 GB and partition 3 which is space for my data so I click on partition 2 and I get a message "We couldn't create a new partition or locate an existing one. For more information se the setup log file?"
Don't create and partition the 200 Gb partition, just leave it as unallocated. Select it for the install location and Windows will create what partitions it needs automatically. It may be having an issue trying to create the EFI partition. On a clean install I delete all the partitions except my data partition and just leave the space unallocated. Windows then creates what it needs automatically. Recovery > System > EFI
Quote