Windows 10 UEFI - Secure Boot Issue

[Heat_Fan89]

I posted this question on the Lenovo forums and still no replies so I thought i'd ask it here in case someone knows. Up until recently if I reinstalled Window 10 using a USB Flash drive it would install it with UEFI enabled, meaning if I created a new disk partition and formatted the HDD or SSD, the Windows 10 installer would create a "Recovery Partition".

That no longer happens. I'm now seeing a Legacy partition called "Reserved". The only thing I can think of that started this problem is the Windows 10 Lenovo Vantage App downloaded and installed a few BIOS updates within the last 6 months. I'm thinking it broke something in the BIOS. I say that because I can boot and install off a Legacy DVD drive and install Windows 10. In the past when UEFI was working properly it displayed and error message that the "created media required UEFI/Secure Boot" to install Windows 10.

What's strange is, if I installed Windows 10 from either a USB or DVD, it installs the default version of Windows 10 that came with my PC. That's what UEFI/Secure Boot does since there are NO associated Windows 10 Product Keys visible on the PC. It's all written on the BIOS.

So I have tried several ways to create a UEFI Windows 10 Bootable Media.

1) Windows 10 Media Creation Tool
2) Rufus Media Creation tool with UEFI - Non CMS enabled.

Anyone have any ideas? This problem is strange indeed.

 

[bogdanw]

Usually, Windows installation media (DVD or USB) can be used for both modes, BIOS and UEFI. But you have to select the desired mode at start-up. I'm not sure what key is assigned to your Lenovo model, but try with F10 or F12 to select the UEFI USB. Sorry for the low quality image

 

[Heat_Fan89]

Thanks for the reply and I had tried that a few days ago and I didn't mention it, my bad. I also removed the bootmgr file and left just bootmgr.efi to force it into UEFI mode. That didn't work either.

My gut tells me and it's not the 1st time Microsoft having a faulty installation process, is that the Media Creation Tool could be the problem and for some reason my PC doesn't make the switch to UEFI during installation. A few years ago, I had a couple of laptops that would hang during the install process and couldn't perform a clean install of Build 1703. I had to install the previous OS, then upgrade the OS to that latest Build within Windows. The following Build 1709 fixed that problem. I also looked at the BIOS settings and everything was in order. I even loaded the default settings and still no go.

I may have to be patient and see if Build 2009 puts everything back the way it should because the Media Creation Tool is also updated to download the latest Build from Microsoft's website.

 

[Heat_Fan89]

I found the problem and I had a suspicion as to what was causing it but couldn't prove it until I got a hold of another Windows 10 machine. Microsoft strikes again !

I was able to find a copy of Build 1903 and I was able to enter and install automatically Build 1903 in UEFI/Secure Boot mode. So it's what I was leaning on, it's either a crappy bootloader issue because of the Media Creation Tool, Microsoft made or the drivers in Build 2004 are horrid.

So hopefully this problem will be caught and rectified in Build 2009.