# How to make F12 Boot Menu work



## MikeInMexico (Jul 24, 2010)

I have two hard drives, one with a Windows 10 installation, the other has Linux Mint. I was assuming that I could use the F12 boot menu to select which one I want. No such luck. What actually happens is that with UEFI boot mode, it will boot only windows, and in fact that's the only option that shows on the F12 menu.
If I want to boot Linux, I have to switch to Legacy boot mode, and then the F12 shows the options, but it will only boot Linux, regardless of what I select on the F12 menu.
So my only method to switch systems is to change boot mode between UEFI and Legacy. F12 gives me no control whatsoever.
Any suggestions? Is this the right forum?


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## spunk.funk (May 13, 2010)

Windows 10 was installed on a drive Initialized as *GPT* for UEFI Bios. Mint was installed on a drive Initialized as *MBR* (ie) CSM/Legacy. The best option is to_ Initialize_ the Linux drive to GPT in Windows using* Diskpart* and then reinstall Linux from a USB Flash drive. You would have to rebuild your Linux boot key using Rufus. In Rufus, under *Partition Scheme*, take the drop down arrow and choose* GPT* and not MBR, Once installed., At that point, at bootup, it should load the GRUB boot loader and give you a choice to boot into Windows or Mint every time.
You can try converting the Linux drive to GPT, but that won't give you the GRUB Boot loader.


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## MikeInMexico (Jul 24, 2010)

spunk.funk said:


> Windows 10 was installed on a drive Initialized as *GPT* for UEFI Bios. Mint was installed on a drive Initialized as *MBR* (ie) CSM/Legacy. The best option is to_ Initialize_ the Linux drive to GPT in Windows using* Diskpart* and then reinstall Linux from a USB Flash drive. You would have to rebuild your Linux boot key using Rufus. In Rufus, under *Partition Scheme*, take the drop down arrow and choose* GPT* and not MBR, Once installed., At that point, at bootup, it should load the GRUB boot loader and give you a choice to boot into Windows or Mint every time.
> You can try converting the Linux drive to GPT, but that won't give you the GRUB Boot loader.


Thanks for the fast response. I initialized the Linux hard drive to GPT (Using Mini-tool, I'm not up for command lines). I rebuilt the Flash drive using Rufus as suggested. Then I reinstalled Linux.
Result: I still get no option to boot the Linux drive in the F12 menu. So I tried switching from EUFI to Legacy ..Now I just get "No bootable device". So in fact I have taken a step backwards. No way to boot from the Linux drive.


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## spunk.funk (May 13, 2010)

You would not get a choice of Linux at the F12 menu, you just get to choose to boot from HDD, USB or CD. If you installed Linux while the Windows drive was still attached and powered on, Mint should have installed Linux GRUB Boot loader menu, which should be the first thing you see when you boot the computer. That would give you the option to boot into Windows or Linux. If not, you will have to go into Linux terminal and make it visible Grub Boot Menu — Linux Mint User Guide documentation


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## MikeInMexico (Jul 24, 2010)

It seems that it didn't work that way. The Windows drive was powered on during the Linux install, but I have no Linux option on the F12 menu. Of course, since I now have no way to boot Linux, I can't do anything with the Linux terminal.
Thanks for your help anyway.


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## spunk.funk (May 13, 2010)

Again, you will never have the option to boot into _*ANY *_*O*perating *S*ystem from the F12 menu. The F12 menu is used to choose which _drive_ to boot from (ie) HDD, CD/DVD or USB. It doesn't give you an option to choose a different HDD if you have more then one. 
Also, As previously stated, you have to _Reinstall _Mint after converting the drive from MBR to GPT. If you are not getting an option to boot into Linux, the install wasn't completed.
In Windows, press the* Windows* Key*+X *and choose *Disk Management *or in *Minitool *and Confirm that the Linux drive is _Initialized _as GUID (GPT) In Disk Management right click the Disk # in the lower pane and choosing *Properties/Volumes.* Once confirmed
Then Boot from the Mint USB Flash drive you created in *Rufus* and choose to *Install Mint* to the Linux drive. When it finishes and reboots, you will have the *GRUB *menu when you start the computer *Not* under the F12 menu.


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## Stancestans (Apr 26, 2009)

Some systems will let you choose which HDD or SSD to boot from in the F12 boot menu, while some don't. In such systems, the HDD option is expandable and shows the separate bootable HDDs. Some systems won't list the drive if it isn't recognised as a valid boot device (has no boot partition). Some (UEFI BIOS) have an option to add additional boot entries, which appear in the F12 menu. You can add the Grub EFI bootloader in the Linux EFI system partition this way if it isn't automatically detected and added during POST.


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## MikeInMexico (Jul 24, 2010)

Yes I've done exactly what spunk.funk says (twice). I still don't get the GRUB menu on restart. I wish I could add boot entries to the UEFI, but I don't think this (ACER) BIOS allows this. 
I find the whole alphabet soup (GPT, MBR, UEFI, GRUB, LEGACY ... ) extremely confusing. I will keep researching. I don't think I'm particularly dumb (I wrote code for a computer using vacuum tubes in the early 1960's), but this has got me very frustrated. Thanks for your responses.


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## Stancestans (Apr 26, 2009)

Consider using EasyBCD to manage boot menu entries.


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## spunk.funk (May 13, 2010)

EasyBCD is the quickest and easiest way to add Linux to the Boot menu.


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## MikeInMexico (Jul 24, 2010)

Stancestans said:


> Consider using EasyBCD to manage boot menu entries.


Thanks. I tried that, but it tells me that since one of my systems is UEFI, many functions are disabled (including adding a Linux entry)


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## spunk.funk (May 13, 2010)

You may have to revert Windows to CSM/Legacy Mode reinstall Linux with an MBR Initialized Boot key and drive. 
Here are some other tips EasyBCD and UEFI


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## Stancestans (Apr 26, 2009)

MikeInMexico said:


> Of course, since I now have no way to boot Linux, I can't do anything with the Linux terminal.


Boot from your Linux Mint installation media in UEFI mode and choose the option to *Try Mint*. This will load a Live session from which you can access the Terminal and reinstall Grub EFI. See https://askubuntu.com/questions/831216/how-can-i-reinstall-grub-to-the-efi-partition. Install GRUB on the EFI system partition of the drive containing Mint, i.e */dev/sdXX*



MikeInMexico said:


> Thanks. I tried that, but it tells me that since one of my systems is UEFI, many functions are disabled (including adding a Linux entry)


Install/reinstall and update GRUB EFI then add the Windows boot manager entry to it if it isn't automatically detected and added during the Grub install.


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## MikeInMexico (Jul 24, 2010)

Thank you for all your responses. I really appreciate it. 
I have given up the Linux idea. I do try various distros out about once/year to see if it offers me a viable escape route from Microsoft. All attempts still seem to end up with some form of arcane command line stuff, which I consider to be 20-year old technology. So sad.
Thanks again.


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## Stancestans (Apr 26, 2009)

Using a virtual machine is a great way of testing distros.


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## spunk.funk (May 13, 2010)

As stated, Using a Virtual Machine, like Oracle VM VirtualBox is a great way to try different OS's, Linux Distro's or older versions of Windows while you are still in Windows 10.
If you want to master Linux you have to learn the Terminal (command line stuff) which is not 20 year old technology, but actually is the future.


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## MikeInMexico (Jul 24, 2010)

OK, I've found an easy way to do what I wanted. Create the Mint live on flash drive, Then use Clonezilla to clone it to the Internal HD, where I wanted it in the first place. Now I get the option of Windows or Linux on the f12 menu. How easy was that?
Thanks for all your attention. Much appreciated.


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## simonss22 (Nov 24, 2020)

> I have two hard drives, one with a Windows 10 installation, the other has Linux Mint. I was assuming that I could use the F12 boot menu to select which one I want. No
> 
> such luck. What actually happens is that with UEFI boot mode, it will boot only windows, and in fact that's the only option that shows on the F12 menu.
> 
> ...


If nothing works try updating your BIOS


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## oscer1 (Jan 27, 2010)

simonss22 said:


> If nothing works try updating your BIOS


Was solved at post 17


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## MikeInMexico (Jul 24, 2010)

OK here's the final solution. My idea in post 17 was fine as far as it goes, but I was still in the "pre-install" mode, which has a lot of limitations. The final solution had nothing to do with re-installing Grub or anything else. It was all in the BIOS.

Boot to the BIOS (F2 in my case)
On the Security tab, set an admin password
On the boot tab, disable secure boot
On the security tab, go to "select trusted UEFI file"
select the HD with the Linux install
Select an EFI file, give it a name (Linux?)
(This last step may need some trial and error, since several EFI files are available, and not all of them work)
- Save and exit

Now, "Linux" will show up on the F12 boot menu, along with Windows boot manager.
Job done!
Thanks for your responses.


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