TeraByte Unlimited

I want to create a new multiple boot system on a new Computer with UEFI-Bios. I need to have 3 win10 systems on 3 different HDDs.

I installed BUI and one win10 on the first HDD from a Microsoft win 10 stick. This partition starts properly. Now I copied this win10 installation to each of the both other HDDs. But no sucess to start them. How do I get them to run?

alfred,

If your ESP is 100 MiB it isn't large enough to support 3 Win10. I suggest you resize the ESP to 400 MiB and then use fixboot.tbs.

If BIU is installed, fixboot offers to set-up a small configuration for the system in the ESP. It will install only the required files in the Microsoft.xxx folder. This may be enough in most of the case. This minimum configuration requires less than 3MiB of space, instead of the normal 25MiB. In that case, an ESP of 100MiB is enough.

In the meantime I tried to install win10 from the win10-Stick to the next HD like I did with the first sucessful installation of win10. (Before, I deleted the copied version of win10, so the disk was completely clean. The installation process from the stick was interupted after having choosen the partition of the according HDD with the error-message, that the EFI partition wouldn´t have a Fat32 format (which is wrong) and Microsoft continued saying, that I shall format the EFI-partition to the NTFS format.

But not enough troubles: now I have on the primary partion with the working win10: a recovery partition and a second EFI partition (the old one called "EFI System" and the new one called "EFI System partition"). On the former completely free HDD on which I tried to install win10 from the stick with no sucess, I have now an EFI system partition and recovery partition. Now I am completely confused. what to do with this new senseless partitions. (I have for years BootItNG used with no problems for over 15 years on 3 updated computers.).

What to do now?

Does each HDD with a booting OS need an own EFI-partition or are the boot-commands of all OS written written to the EFI partition, which BUI has created on its installation on the HDD:0? Or does each booting OS need an own EFI partitionfor itself? Whats about the "recovery partitions"?

Please see page 59 in the BIU manual regarding installing OS. Multiple ESP can cause installation issues.

Thanks. I erased all HDDs and BUI and started a new attempt with only one ESP. Great sucess.

alfred,

Did you install BIU to a blank drive? This is the best way as the BIU install gives you a 400 MiB ESP which is large enough to support many OS.

So I did. I was to much bound in my thinking at BootItNG. So I did´t understand the workig principle of BUI. Thanks.