Win wont boot when Secure Boot Enabled. Keeps Enab

  friendlyJai 19:37 18 Oct 2017

I recently formatted and reinstalled Windows 10 on my friends laptop. In order to do this I had to convert the GPT to an MBR as would not install otherwise.

To get it to boot from the disk to install Windows I disabled Secure Boot and enabled CSM. However now secure boot keeps enabling automatically and Windows will not boot but goes straight to the BIOS until I disable it again.

I read somewhere that being an MBR might be part of the problem. But as I said I had to convert it to an MBR for it to install. Would converting it back to a GPT solve the problem? Would converting it cause me to loose everything that ive just installed on the Hard Drive?

Thanks in advance James

  BRYNIT 20:29 18 Oct 2017

Have a read of CLICK HERE a little information on UFEI and legacy mode.

If the laptop was originally formatted to GPT it should have installed without problems unless the Windows 10 installation was missing some files. Did you use the Windows creation tool to download Windows 10 before installing on to a DVD or USB. When tried to install Win 10 did you delete all partitions first or was the HDD already formatted.

  friendlyJai 09:27 19 Oct 2017

Yeah was originally formatted with GPT. It had Windows 10 on it already but froze at the login screen. I downloaded Windows 10 (years ago) and installed it to a DVD.

When I tried to install Windows 10 the Hard Drive was partitioned but just tried to install it on the one I formatted that Windows was installed on before. Then Windows complained that it could not install as was a GPT partition. SO I used cmd to convert it to a MBR, which also removed all the partitions. Windows then installed no problem. But secure boot keeps enabling automatically and then just goes straight to BIOS.

Is there a workaround? Such as having a file run when laptop is turned on so that it automatically disables Secure Boot and Enables CSM, so that Windows will then boot?

I will have a read of your link now, too.


  rdave13 09:52 19 Oct 2017

The mistake you've done is to install Windows on the C: partition only and so you've left the GPT EFI system partition there. That will trigger the uefi screen to disable secure boot. Well.. that's my theory. Download Minitool partition wizard (free) to have a look at your partitions. Disk management isn't as thorough.

Personally I would start again. Convert the disk back to GPT, disable CSM and enable secure boot, then download and create a fresh bootable DVD of the latest Windows 10 from here . During the install when you get to the options to delete partitions I would delete them all and do a fresh install. That's just my preference. I don't know what would happen if you have the EFI system partition still there and you used MiniTool to delete it.

  friendlyJai 10:56 19 Oct 2017

Thanks, so in future best to remove any partitions first then? Ive downloaded the MiniTool and its showing 500MB System Reserved and the rest just the C: Drive. If I attempt to delete the system reserved data then I get a warning that may not boot. I don't really want to start from scratch as ive spent hours installing programs and getting updates.

Id be happy just have a work around if I can make it so that it always disables Secure Boot and enabled CSM at the start automatically so that windows boots up, would be fine. I know its not getting to the underlining problem but would do for now.

Also just curious I tried to install Windows 7 on it initially as my friend does not like Windows 7 but it kept crashing with the blue screen. Is this because it was orgiginally a Windows 8 laptop or could my disks corrupt? I have a few Windows 7 disks but all do they same thing

Thanks again

  Fruit Bat /\0/\ 19:24 19 Oct 2017

System Reserve contains the WIN 10 boot files in a boot folder.

  Fruit Bat /\0/\ 19:28 19 Oct 2017

It also contains a recovery folder with the winRE environment tools that you need to use to make repairs if it won't boot.

I wonder if you boot to the recovery tools (power on then off after 5 seconds do three times and on fourth attempt it should boot to Advance tools option). Ther you could try doing a startup repair and see if that solves your problems.

  BRYNIT 21:30 19 Oct 2017

If you're doing a clean install I find it's best to delete all partition, this can be done via the installation DVD/USB it should then partition and format the drive before it installs Windows.

  friendlyJai 07:58 20 Oct 2017

Thanks for all your replies. I have given the laptop back to her but she is happy just to keep disabling secure boot each time she turns it on.

Yeah, so next time I will go into the cmd prompt via the DVD and format and delete any partitions first before attempting to install Windows.

There was a similar thread someone I read and they said the following : "Your installation media probably was compatible with CSM/legacy install only.

Either convert to gpt using mbr2gpt utility or reinstall windows in UEFI mode."

First would converting to GPT cause everything to wipe or would it boot as normal? Second, what does he mean exactly by installing in UEFI mode? I thought the only way to boot from the disk was to disable secure boot from the BIOS and boot from the CD.

Thanks again

  friendlyJai 08:12 20 Oct 2017

Ive just read this thread

click here installing Windows on UEFI-based PCs using Windows Setup, your hard drive partition style must be set up to support either UEFI mode or legacy BIOS-compatibility mode.

For example, if you receive the error message: “Windows cannot be installed to this disk. The selected disk is not of the GPT partition style”, it’s because your PC is booted in UEFI mode, but your hard drive is not configured for UEFI mode. You’ve got a few options:"

I did receive that error message saying that its not GPT partition style, so therefore I must have installed it in UEFI mode. So i'm obviously confused about the difference between UEFI mode and Legacy BIOS mode.

I'm going to format another friends desktop PC soon although last time did not have any of these problems (although did not previously have any partitions on). So will take this knowledge from your advice away and use it to practise on it



  rdave13 08:56 20 Oct 2017

GPT/UEFI system is easier than MBR/BIOS i think. Formatting an MBR disk is ok for a fresh install as you start with 'as new' disk with a BIOS system. With a GPT/UEFI I don't see the need as during the install process you get the option to delete all the partitions on the drive individually so you end up with the whole space as unallocated. Ideal for a Windows 10 fresh install as it will create its own needed partitions automatically. Most modern computers come as GPT/EFI now so I don't see the point in running in legacy mode.

Replacing drives to SSDs on a UEFI system I check the drive to see if MBR or GPT. If the new drive is MBR then I use Windows to convert to GPT. Windows erases all the info on the drive (you'll get a warning) which is then ideal to do a fresh install.

I've only got one BIOS/MBR laptop left (9 yrs old) and it's running the skip ahead preview version of 10 quite happily though.

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