Reboot and select proper boot device

[ignorantMan]

I've installed debian 12 on my new ssd.
It worked properly until today, when i turned on my laptop and i got this error on black screen "Reboot and select proper boot device".

Now:
1. I've replaced my ssd with my old hdd with deb11.
2. I've connected my new ssd(with deb12 on it) to the laptop with a USB3>SATA Cable.

I suppose is a grub error. Am i right?
What can i do to solve the problem and put my ssd back into the laptop?

[peer]

I don´t know if this is a grub problem.
I would install supergrub2 on a usb disk (download the usb-image from https://www.supergrubdisk.org/super-grub2-disk/)
With the ssd installed start supergrub2 and then select the installation on the ssd.
Then install grub again.

[Aki]

I've installed debian 12 on my new ssd. It worked properly until today, when i turned on my laptop and i got this error on black screen "Reboot and select proper boot device".
[..]
I suppose is a grub error. Am i right?

No, it is probably a BIOS error (it cannot access the disk).

EDIT: moved to "Hardware" sub-forum.

[ignorantMan]

I've installed debian 12 on my new ssd. It worked properly until today, when i turned on my laptop and i got this error on black screen "Reboot and select proper boot device".
[..]
I suppose is a grub error. Am i right?

No, it is probably a BIOS error (it cannot access the disk).

EDIT: moved to "Hardware" sub-forum.

Why now???

[mrmazda]

Is this a UEFI laptop? How many times did you boot successfully before the failure started? Did it coincide with first removal of the installation media? Had you just made some seemingly immaterial change in BIOS/UEFI setup? The problem could be lack of boot flag anywhere on the new SSD. Without one, it's possible the boot process doesn't get as far as Grub. That message means the BIOS found nothing configured to be bootable.