Windows 10/7 Dual Boot issue

[LordZankon]

So, I have windows 7 already installed and I wish to dual boot for gaming purposes. So i went online and shrank my volume of my micron 500 ssd. After using rufus to convert my usb stick to fat32 and gpt for uefi, I made a partition on my ssd and renamed it windows 10 and it has 192gb. Shoot to installation procedure and I click on partition and i get the error message "Windows detected that the EFI system partition was formatted as NTFS. Format the EFI system partition asFAT32, and restart the installation. I'm attempting to dual boot and not lose data. What should I do here? Should I modify bio settings? Or clone my drive, convert my ssd, put everything back onto my ssd and then attempt the installation again?

Gigabyte GA-Z170X-Gaming 7 ATX LGA1151 Motherboard
i7 6700k (not overclocked)
MSI GTX 1070
Micron 500 SSD (one i wish to dualboot on)
50gb SSD (unused)
and a 6tb TOSHIBA 7200rpm hardsrive

 

[Colif]

you need to set up the bios on motherboard to use legacy boot method only as since you are only using 1 ssd for both win 7 and win 10, you have to stick to mbr or Win 7 won't boot up.

If you were using 2 ssd/hdd then you could let win 10 set up an EFI partiton but win 7 cannot boot off a drive formatted in GPT

 

[LordZankon]

you need to set up the bios on motherboard to use legacy boot method only as since you are only using 1 ssd for both win 7 and win 10, you have to stick to mbr or Win 7 won't boot up.

If you were using 2 ssd/hdd then you could let win 10 set up an EFI partiton but win 7 cannot boot off a drive formatted in GPT

"Windows detected that the EFI system partition was formatted as NTFS. Format the EFI system partition as FAT32, and restart the installation" the same error, I'll look into the motherboard settings once again to make sure its in legacy again.

 

[Colif]

That is strange, you don't normally find an efi partition on a win 7 drive. Is this Win 7 64bit? As it seems that can boot off GPT - https://answers.microsoft.com/en-us/windows/forum/windows_7-windows_install/how-to-clean-install-windows-7-professional-64-bit/c052117c-8faa-4b5b-bd31-30bb9b21a0eb

don't change boot method just yet, make sure you know what it is before swapping in case 7 doesn't boot

Can you show me a screen shot of disk management?

Many of the fixes are just wipe drive and format it again but that is not helpful in a dual boot situation like this, https://superuser.com/questions/965641/convert-ntfs-efi-partition-to-fat32

 

[LordZankon]

That is strange, you don't normally find an efi partition on a win 7 drive. Is this Win 7 64bit? As it seems that can boot off GPT - https://answers.microsoft.com/en-us/windows/forum/windows_7-windows_install/how-to-clean-install-windows-7-professional-64-bit/c052117c-8faa-4b5b-bd31-30bb9b21a0eb

don't change boot method just yet, make sure you know what it is before swapping in case 7 doesn't boot

Can you show me a screen shot of disk management?

Many of the fixes are just wipe drive and format it again but that is not helpful in a dual boot situation like this, https://superuser.com/questions/965641/convert-ntfs-efi-partition-to-fat32

I'm about to feel like an idiot aren't I

 

[Colif]

No, I didn't know Win 7 could boot off an efi partition - its news to me, do you have win 7 64 bit version?
I am curious why you have two EFI partitions as win 10 should use the other one.
Something strange going on here, you shouldn't have 2 recovery partitions either.

have you got backups of all the info you don't want to lose on C? I don't know if its necessary but it might be. Think I need to get a second opinion

 

[LordZankon]

No, I didn't know Win 7 could boot off an efi partition - its news to me, do you have win 7 64 bit version?
I am curious why you have two EFI partitions as win 10 should use the other one.
Something strange going on here, you shouldn't have 2 recovery partitions either.

have you got backups of all the info you don't want to lose on C? I don't know if its necessary but it might be. Think I need to get a second opinion

That second one is made when Windows 10 attempts to install on the partition. Whether or not I make it in Windows 7 or at the time of attempting to install 10. and yes, I have Windows 7 Ultimate 64bit

 

[Colif]

i think the answer is to delete the win 10 partitions already created, leave the space created by the deletion as unallocated space and then run the win 10 installer again. It should create its own partitions with right format. This may leave win 7 unbootable as I assume it should make its own EFI. To fix this you can probably run the bootrec fixmbr command and it should add the win 7 install to the EFI created by win 10

 

[LordZankon]

i think the answer is to delete the win 10 partitions already created, leave the space created by the deletion as unallocated space and then run the win 10 installer again. It should create its own partitions with right format. This may leave win 7 unbootable as I assume it should make its own EFI. To fix this you can probably run the bootrec fixmbr command and it should add the win 7 install to the EFI created by win 10

I've already tried the unallocated method, same error message

 

[Colif]

Well, i guess that makes sense, don't need two efi on PC.

I suspect only answer is to delete the EFI that already exists and then install win 10 as it should make its own - I am just working out the safest way to do it.

Deleting EFI system partition will cause installed systems unbootable. So, EFI system partition is usually protected and locked by the Windows operating systems to prevent and avoid accidental deletion of these partitions. That’s why you can’t delete EFI partition using Disk Management tool. But in some special situation, for example, when you uninstalling Windows system, you might want to remove EFI system partition to free up some disk space.

I normally show people the windows steps to do this but for this, you might be best using a program as it lets you clone the EFI before deleting it in case of accidents, and then delete it.

You will then have to install win 10 to get it to create the proper EFI and allow win 7 & 10 to boot again

 

[LordZankon]

Well, i guess that makes sense, don't need two efi on PC.

I suspect only answer is to delete the EFI that already exists and then install win 10 as it should make its own - I am just working out the safest way to do it.

Deleting EFI system partition will cause installed systems unbootable. So, EFI system partition is usually protected and locked by the Windows operating systems to prevent and avoid accidental deletion of these partitions. That’s why you can’t delete EFI partition using Disk Management tool. But in some special situation, for example, when you uninstalling Windows system, you might want to remove EFI system partition to free up some disk space.

I normally show people the windows steps to do this but for this, you might be best using a program as it lets you clone the EFI before deleting it in case of accidents, and then delete it.

You will then have to install win 10 to get it to create the proper EFI and allow win 7 & 10 to boot again

I'll give that a try today and get back to you on the progress!

 

[LordZankon]

The issue was hard drives, for future reference, if installing another OS of Windows while using Windows 7/10, make sure ALL other hard drives are disconnected and it will fix 99% of errors