On Sun, 4 Oct 2026 17:06:03 -0400
MartinGary Padgett <martingarypadgett@gmail.com> wrote:

Cannot install Debian 12 'Bookworm' in my desktop computer. (Not yet
ready to learn 13 'Trixie'.)

I haven't seen much difference, so I suggest you start with trixie.
Also, it is possible that whatever is causing your problem has been
fixed or avoided in the newer Debian Installer (d-i).

To do so I need to find somebody with a
computer to download file 'debian-12.15.0-amd64-netinst.iso' and then
'burn' it on either a DVD or CD optical disk. The nearest other
computer is owned by one of my grandson, a 'MAK laptop'. He
downloaded the file and 'burned' it to a DVD using a portable optical
disk drive. Then I opened the desktop, put the disk in the desktop
optical drive, and restarted it. All that happened: the BIOS
appeared. That is all.

Having downloaded the iso, did your grandson then verify the image with shasums, and verify the checksums with the Debian GPG key?

Having burned the image, did he then mount the CD and checksum the
contents?

root@testing:~# mount /media/cdrom
mount: /media/cdrom0: WARNING: source write-protected, mounted read-only. root@testing:~# cd /media/cdrom
root@testing:/media/cdrom# md5sum --q -c md5sum.txt
root@testing:/media/cdrom#

In Unix fashion, if the CD is good, you should see no output from this.

I still have an older optical disk for Debian 12 dated 2015-06-19.
This one is faulty and so cannot complete the installation. It is
however useful for testing subsequent installations. This one did not
open the BIOS; instead right after the desktop opened a full blue
screen appeared with the word ERROR at the top. The next line said 'Verification failed: (Ox1A) Security Violation. Then on hitting the
OK in the middle of the screen the BIOS returned.

So why would the desktop reject the current installer but accepted the obsolete one even if it was incomplete?

Methinks you'll have to ask your BIOS vendor that. Are you sure it a
BIOS machine, and not a UEFI machine? Which machine is it, and have you
looked it up on https://linux-hardware.org?

What has to be done to activate the current one?

One final comment, I live in Toronto, Canada. When these problems
emerged, I tried unsuccessfully to find people in Toronto who could
help me with or without payment. If such a person or persons exist, I
would like find out how to connect with them.

There may be a Linux Users Group in or near Toronto. A bit of creative searching should turn one up. Or see the recent discussion on this list
for other ideas.


--
Does anybody read signatures any more?

https://charlescurley.com
https://charlescurley.com/blog/

--- PyGate Linux v1.5.19
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

It is important to know that the "ISO" image files for *ALL* current (and generally recent vintage) Linux install images (all distros) not only work on optical disks (either CDs or DVDs) but also on flash drives. BUT it is important to image it onto the flash drive, not just copy onto a stock drive's file system. This can be done with dd on a Linux machine, but requires a "special" program under MS-Windows. Modern computers ("PC" types AND Macs) under stand how to boot these images from flash drives (might require some fiddling with UFI secure boot settings. etc.).

At Sun, 4 Oct 2026 16:44:35 -0600 Charles Curley <charlescurley@charlescurley.com> wrote:

On Sun, 4 Oct 2026 17:06:03 -0400
MartinGary Padgett <martingarypadgett@gmail.com> wrote:

Cannot install Debian 12 'Bookworm' in my desktop computer. (Not yet
ready to learn 13 'Trixie'.)

I haven't seen much difference, so I suggest you start with trixie.
Also, it is possible that whatever is causing your problem has been
fixed or avoided in the newer Debian Installer (d-i).

To do so I need to find somebody with a
computer to download file 'debian-12.15.0-amd64-netinst.iso' and then 'burn' it on either a DVD or CD optical disk. The nearest other
computer is owned by one of my grandson, a 'MAK laptop'. He
downloaded the file and 'burned' it to a DVD using a portable optical
disk drive. Then I opened the desktop, put the disk in the desktop
optical drive, and restarted it. All that happened: the BIOS
appeared. That is all.

Having downloaded the iso, did your grandson then verify the image with shasums, and verify the checksums with the Debian GPG key?

Having burned the image, did he then mount the CD and checksum the
contents?

root@testing:~# mount /media/cdrom
mount: /media/cdrom0: WARNING: source write-protected, mounted read-only. root@testing:~# cd /media/cdrom
root@testing:/media/cdrom# md5sum --q -c md5sum.txt root@testing:/media/cdrom#

In Unix fashion, if the CD is good, you should see no output from this.

I still have an older optical disk for Debian 12 dated 2015-06-19.
This one is faulty and so cannot complete the installation. It is
however useful for testing subsequent installations. This one did not
open the BIOS; instead right after the desktop opened a full blue
screen appeared with the word ERROR at the top. The next line said 'Verification failed: (Ox1A) Security Violation. Then on hitting the
OK in the middle of the screen the BIOS returned.

So why would the desktop reject the current installer but accepted the obsolete one even if it was incomplete?

Methinks you'll have to ask your BIOS vendor that. Are you sure it a
BIOS machine, and not a UEFI machine? Which machine is it, and have you looked it up on https://linux-hardware.org?

What has to be done to activate the current one?

One final comment, I live in Toronto, Canada. When these problems
emerged, I tried unsuccessfully to find people in Toronto who could
help me with or without payment. If such a person or persons exist, I
would like find out how to connect with them.

There may be a Linux Users Group in or near Toronto. A bit of creative searching should turn one up. Or see the recent discussion on this list
for other ideas.

--
Robert Heller -- Cell: 413-658-7953 GV: 978-633-5364
Deepwoods Software -- Custom Software Services
http://www.deepsoft.com/ -- Linux Administration Services
heller@deepsoft.com -- Webhosting Services


--- PyGate Linux v1.5.19
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

I believe one *has* to turn off Secure Boot when booting from any sort of removable media. I also believe one Linux has been instally onto the local hard drive, it should be possible to turn Secure Boot back on -- I believe you need to be sure the installer does what is needful with the UFI boot setup (I believe the installer does this or asks about this).

At Mon, 5 Oct 2026 09:22:42 -0500 nwe <nwe@gitcoding.net> wrote:

On 10/4/26 4:06 PM, MartinGary Padgett wrote:

(Not yet ready to learn 13 'Trixie'.)

I don't know that there would be anything 'new' for a user to learn
here. Is there noticeable difference to the interface?

Then I opened the desktop, put the disk in the desktop optical drive,
and restarted?ÿit. All that happened: the BIOS appeared. That is all.

I still have an older optical disk for Debian 12 dated 2015-06-19.

This one did not open the BIOS; instead right after the desktop opened
a full blue screen appeared with the word ERROR at the top. The next
line said 'Verification failed: (Ox1A) Security Violation. Then on
hitting the OK in the middle?ÿof the screen the BIOS returned.

Do you have secure boot feature switched off in the bios? In the past
I've had linux fail to boot, showing some kind of security errors if
secure boot was switched on.

As far as I know, secure boot prevents your pc from booting any os
unless it is enrolled in the secure boot. I think Debian supports secure boot, but I never bother with it, instead I switch it off in the bios.

Attachment saved: /usr/tmp/1791213287/Email/13/Attachments/OpenPGP_signature.asc (application/pgp-signature)

--
Robert Heller -- Cell: 413-658-7953 GV: 978-633-5364
Deepwoods Software -- Custom Software Services
http://www.deepsoft.com/ -- Linux Administration Services
heller@deepsoft.com -- Webhosting Services


--- PyGate Linux v1.5.19
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

martingarypadgett@gmail.com wrote:

Cannot install Debian 12 'Bookworm' in my desktop computer. (Not yet ready
to learn 13 'Trixie'.) To do so I need to find somebody with a computer to >download file 'debian-12.15.0-amd64-netinst.iso' and then 'burn' it on
either a DVD or CD optical disk. The nearest other computer is owned by one >of my grandson, a 'MAK laptop'. He downloaded the file and 'burned' it to a >DVD using a portable optical disk drive. Then I opened the desktop, put the >disk in the desktop optical drive, and restarted it. All that happened: the >BIOS appeared. That is all.

There are multiple possible ways this could have happened - maybe
faulty media, or the ISO was not written correctly. Or maybe your
machine can only boot CD media andn won't boot DVD media - we don't
have enough information to go on here immediately.

I still have an older optical disk for Debian 12 dated 2015-06-19.

Are you sure of thate date? *2015* is 11 years ago, while the first
release of Debian 12 (aka "bookworm") was June 2023.

This one is faulty and so cannot complete the installation. It is
however useful for testing subsequent installations. This one did not
open the BIOS; instead right after the desktop opened a full blue
screen appeared with the word ERROR at the top. The next line said >'Verification failed: (Ox1A) Security Violation. Then on hitting the
OK in the middle of the screen the BIOS returned.

So what this means is that your system is booting using UEFI, and you
have Secure Boot enabled. Older versions of the GRUB bootloader (used
on both our installation media and on installed systems) have been
blocked from execution on Secure Boot systems due to security holes
that were found in it. You will need to use a newer installation
medium here where those bugs are fixed. That includes the 12.15.0
version mentioned above, or (better) 13.7.0 (aka "trixie") which is
our current stable release and better supported.

So why would the desktop reject the current installer but accepted the >obsolete one even if it was incomplete?

See my guesses above.

What has to be done to activate the current one?

As your system is modern enough to be using Secure Boot, it will
definitely be capable of booting directly from a USB stick as people
elsewhere in this thread have suggested. I'd suggest trying one of
those instead as it's much easier and faster to use than a CD/DVD
these days.

The Debian installation guide chapter at

https://www.debian.org/releases/trixie/amd64/ch04s03.en.html

might help you here.

--
Steve McIntyre, Cambridge, UK. steve@einval.com Can't keep my eyes from the circling sky,
Tongue-tied & twisted, Just an earth-bound misfit, I...

--- PyGate Linux v1.5.19
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

heller@deepsoft.com wrote:

I believe one *has* to turn off Secure Boot when booting from any sort of >removable media. I also believe one Linux has been instally onto the local >hard drive, it should be possible to turn Secure Boot back on -- I believe you
need to be sure the installer does what is needful with the UFI boot setup (I >believe the installer does this or asks about this).

No, you could not be more wrong here. All of Debian's current
installation and live media will happily boot as removable media on
systems with Secure Boot enabled.

There's a lot more information about UEFI and Secure Boot in Debian in
the wiki:

https://wiki.debian.org/UEFI
https://wiki.debian.org/SecureBoot

--
Steve McIntyre, Cambridge, UK. steve@einval.com Can't keep my eyes from the circling sky,
Tongue-tied & twisted, Just an earth-bound misfit, I...

--- PyGate Linux v1.5.19
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)