Re: Converted MBR to GPT and menu is gone, can't use grub-reboot either

[Pascal Hambourg]

On 18/02/2023 at 11:45, Michael D. Setzer II wrote:
> Not sure if this might be issue, but I ran into an issue
> recently that had me very confused.

Nothing to be confused about in what you wrote.

> Had a Dell computer with Windows 10
(cut irrelevant stuff)
> decided to add Fedora 37 to
> drive. Booted from the install usb (didn't realize it
> booted from uefi), so when did the install it setup UEFI
> installation on the free space of drive.

As expected. Didn't the Fedora installer warn about an existing OS using 
legacy boot and offer to switch to legacy install ? The Debian installer 
would have.

> on reboot, it showed the Fedora 37, but no
> reference to the windows 10?

As expected. An EFI boot loader cannot chainload a legacy boot loader.
If you want to boot Windows from GRUB, you need to install GRUB for 
legacy boot. Or convert Windows to GPT+UEFI, but that may ruin Fedora.

> Have
> been told the install looked at boot media type, and used
> that??

The installer usually sets up the installed system to boot in the same 
mode as itself was booted.

> So, don't know if you might have a disk with both legacy
> and UEFI setup??

It is now rather common that GNU/Linux distribution installers can be 
booted in legacy and EFI modes.