Dual boot w10 and w7 problem

[michaelmk86]

I have two partitions in my SSD, on the first I have w7, and the second partition is empty (trying to install w10)

I have try to use:

bootable usb stick created with MediaCreationTool from microsoft
bootable usb stick created with Rufus in GPT partition scheme for UEFI
bootable usb stick created with Rufus in MBR partition scheme for UEFI
bootable usb stick created with Rufus in MBR partition scheme for BIOS or UEFI

in all the cases, when I try to install w10 the following message appears:

"windows cannot be installed to this disk. the selected disk has an MBR partition table. On EFI systems, Windows can only be installed to GPT disks."

 

[Colif]

The error isn't the USB, its the hdd. And your bios in a way

Win 10 uses GPT format for its hard drives and won't fresh install onto a MBR disc
Win 7 uses MBR and cannot fresh install onto a disc using GPT, or boot from one for that matter.

See the problem? the reason it is doing this is it recognises your bios as being UEFI and Win 10 will always insist on GPT format if it sees an UEFI bios. If you had an older style motherboard it would happily install itself on MBR as it has no choice.

the easiest answer is to put both an a separate hard drive, then they are happier.

 

[michaelmk86]

I don't have a separate drive so that is not an option.

if I disable the UEFI on my motherboard will this work?

 

[Colif]

If you enable CSM it may let you install win 10 as MBR.

GPT allows access to bigger hdd than MBR disks so one day you may want to change across as MBR cannot access discs bigger than 2.2gb. With Seagate announcing 10tb HDD already its days are numbered.

 

[michaelmk86]

if enable CSM, I will not have any problem with my existing w7 install?

btw I had seen some guides on how to convert existing w10 installation from MBR to GPT, so if in the future I need a bigger storage I sued be able to do that?

 

[Colif]

CSM matches the way Win 7 boots so it will be fine.

 

[michaelmk86]

With CSM enable I was able to install w10 just fine, however it didn’t create a dual boot screen at the start so every time the pc boots it goes strait to w7 without asking me to select os.

 

[Colif]

this might help you boot into win 10: http://www.thewindowsclub.com/repair-master-boot-record-mbr-windows

Use the win 10 installer for the above as win 7 installer in unlikely to fix it.