22.04 LTS to 24.04 LTS Upgrade - Removed OS Boot Load Choice

**oldfred** · 4 Weeks Ago

Issues may be UEFI vs BIOS/CSM/Legacy.

Windows 7 normally was installed in BIOS mode with MBR partitioning. But later versions had UEFI boot with UEFI Secure boot off.
There also were instructions back then on converting early Windows 7 installer to UEFI by adding ESP & UEFI boot files to ESP.
Newer versions of Windows could be installed in BIOS mode to MBR drives, but Microsoft primarily allowed that in beginning, so very large users with older BIOS only systems could install Windows 8. Systems starting in about 2020, may still say "BIOS" but are UEFI boot only.

Microsoft requires gpt partitioning for UEFI boot, Ubuntu does not, but maybe should. Part of issue is conversion from MBR to gpt totally erases a drive in most cases. Windows and Linux have gpt to MBR conversion tools, but really good backups required. Multiple posts where users tried conversion and it did not work. But a few posted they did have it work.
XP did not work with gpt, but when I retired XP, I started to convert drives to gpt. All new & totally reformatted drives then were made as gpt, including most larger flash drives. Have used gpt with Ubuntu for both BIOS & UEFI boot.

**vector3** · 4 Weeks Ago

This makes me think more information regarding my laptop is needed. What else can I do?

I am attempting to confirm whether if my BIOS is Legacy or UEFI but I had to ask on the Thinkpad forum to be certain. I do know the laptop I prepared the rescue CD with has UEFI BIOS because it shipped with Windows 8. We chose the optional downgrade to Windows 7. Would this influence the properties of the rescue disk?

**oldfred** · 4 Weeks Ago

If specs were for Windows 8, then UEFI. But some early UEFI had issues, even with Windows, so some users installed Linux in old BIOS boot mode.
Microsoft required vendors to install Windows 8 in UEFI boot mode to gpt partitioned drives.

But the downgrade to Windows 7 could be UEFI or BIOS.

**vector3** · 4 Weeks Ago

I checked to see for myself and this BIOS is in Legacy mode so I have to suspect the 'donor laptop' factor has no impact. I am still using the original Hitachi THHN SSD.

**vector3** · 4 Weeks Ago

Two additional ideas came to me since my last post above.

First, is it feasible that I am misinterpreting my observations since this issue occurred ~3 weeks ago? By this I mean am I overlooking the time delay between the Thinkpad startup screen and the display of the ubuntu startup screen. I have acknowledged this delay but perhaps insufficiently. My recent efforts with the X201 caused me to consider if the GRUB menu is simply not being displayed. I realize the report from Boot-Repair I provided and the results of the commands I have executed do not present a positive state for GRUB and or the Windows MBR but I began to wonder if I could simply find a way to display GRUB it may offer me something.

Second, should I begin searching for a means to examine the MBR?

**oldfred** · 4 Weeks Ago

The Boot-Repair report shows what is in MBR.

If BIOS boot, you can press & hold shift key from vendor logo until grub menu would normally appear.
If UEFI boot, you press escape key, often have to press several times. Getting timing correct can take several tries.

You can change grub setting to always show grub menu. I do that but reduce default time from 10 to 3 sec.
If booting:
Change these:
sudoedit /etc/default/grub
GRUB_TIMEOUT_STYLE=menu
GRUB_TIMEOUT=3
then
sudo update-grub

If not booting you can edit /boot/grub.cfg, the one that says do not edit as every kernel, grub update or some other changes will rewrite it.

**vector3** · 4 Weeks Ago

That was it! Forgive my offer to buy you a coffee given the measure of proficiency within this forum but I had to offer you something. However, it was tapping the escape key three times that allowed the GRUB menu to be displayed. This have been the problem since it first appeared following the upgrade. Windows loaded successfully with this probe of my issue. I will restart the system to Ubuntu and edit grub.cfg as you suggest.

Edit - Editing grub.cfg went fine but saving the change did not. I still have the ability to display the GRUB menu by careful timing of the escape key but I was unable to load grub.cfg using sudoedit /etc/defaut/grub when I opened terminal a second time to confirm the change occurred. Terminal tells me grub does not exist. How do I correct this misstep?

Solved! GRUB menu is displayed and both OS's load successfully.