I need some help with a bit complex Windows 10 dual boot situation..

I think that i recreate my plans, and go for a solution in my situation..

I am going to put a 2TB M2 in the laptop instead of the 4TB M2.
So i can make both installations just MBR Legacy, and then i am out of trouble, only a bit less space.
I think it is what it is! Otherwise i will keep getting issue with the GPT / MBR combination..

And sure.. 2TB is also a lot!! The reason i wanted double the size is (ofcourse that i already have the harddisk) but also that i use software for all different brands of cars.. And most of them work with flash files to reflash modules in cars.
And when i talk only about BMW for examle, the full flash files are already 550GB!
When i add Mercedes, another 400GB can be count up!
When i add Volkswagen, Audi, etc.. i also 200GB+

And i am Chiptuner, so i have lots of stock files, atleast 300GB.. So now i have let you know why i preffered the 4TB..

But i can ofcourse on the other 2TB drive with Windows 7 32bit also put a lot flash files on it, so i go and do it like this!

Side note:
The reason i bought the Dell 5580 is because it is a fantastic model!! It has already M2, and the Skylake processor which is still capable for Windows 7. And furthermore it has an backlight keyboard, and just still NORMAL mouse buttons! And very long battery life!

Thank you everybody! The 2TB M2 is already ordered!

But when i wanted to boot in Windows 7 32 bit, i have to push the F12 button on startup, and select the internal drive by the Legacy boot options..

So my questions:

- I don't know if i can somehow get a Boot menu with this setup?

I have a vague recollection of doing it a while ago. I was using 64 bit win7 not sure if that made any difference.

I was able to add the win7 entry to the bcd store on the gpt disk.

the win7 entry needs to point at winload.exe ( not winload.efi ) on the win7 partition on the mbr disk.

I did it manually, but you could try using win10 bcdboot.exe and see if that does it.

From within windows 10 at admin cmd prompt:

bcdboot win7partitionletter:\windows /f bios

for example
if win 7 letter is j when seen from booted win10

bcdboot j:\windows /f bios

I actually managed to establish an MBR-32/GPT crossover.

There ya go.

Sure. It reboots.

Well, after all the topic is how not to have to

pveeningen said:

push the F12 button on startup

which makes adding the GPT OS to the MBR Boot Manager a somewhat experimental suggestion that is not so much about the pros and cons of dual booting in general.

So it works in both directions:
1) winload.efi ==> BIOS Bootmanager
2) winload.exe ==> EFI Bootmanager

I tried it out a long time ago. If I remember correctly efi boot manager can start winload.exe but not the other way round. I can't recall which version of boot managers I was using.