1. Install Win7, works, etc.
2. Install Kubuntu via USB drive.
3a. Reboot and Select proper Boot device or Insert boot media in selected boot device and press a key -or-
3b. Reinstalls Kubuntu.

NO Win7, NO Kubuntu, NO GRUB
Help!
(Used Rufus 3.1 to create the bootable USB drive w/ 18.04 ISO)
(UEFI bios, MBR HDD)

Is this message appearing directly after POST? If sounds as if you are booting with the installation USB drive still inserted. If so, remove it, start the machine, and tell us what happens then.

If not, please provide more detail and perhaps a photo of the "Select proper boot media" message (if the click the "Go Advanced" button at the bottom of the compose post screen to the right of the "Post Quick Reply" button, you will be taken to a screen at which you can add attachments).

Installation USB drive was removed for 3a. Upon reset, it could not find its boot medium.
I left the drive in for 3b, to see if that resolved the missing boot medium. It didn't.

I've successfully installed Kubuntu by itself, and GRUB shows up, with a slot for Win7 (!?).
In researching multi-boot, it was mentioned that UEFI + GPT are required. Apparently, my Win7 will NOT install on GPT, and requires MBR. Still looking for a solution.

As I recall, UEFI was not a thing when Windows 7 came out. UEFI, aka "Windows secure market share," came along with Windows 8.

My best guess at this point is that your GRUB is borked. Have you tried an update GRUB? https://howtoubuntu.org/how-to-repai...ubuntu-live-cd

Hi:

frankbell is right. UEFI wasn't an issue with Windows 7. Folks didn't have to deal with the UEFI and secure boot stuff till Windows 8.

Boot into Kubuntu open your terminal and run:
It should pick up Windows 7 and add it to your Grub Menu.

Is your Windows 7 partition on a separate HDD?

...alternatively, make a live cd/usb from this: https://www.supergrubdisk.org/catego...rescatux-beta/
and use the "grub recovery" function therein.
has helped me many times.

A default install of windows 7 would be Legacy rather than UEFI although it is possible to install 7 UEFI/GPT. Any windows install using GPT will need to be UEFI. Did you install Kubuntu UEFI/GPT?

I'm not sure what the "it" you are referring to is. You had to change boot priority in the BIOS to boot from the usb and of course, change it back to boot from the hard drive.

What does "slot" mean? Do you see an entry in Grub for windows 7? You can determine whether you have Kubuntu EFI by booting the install usb and opening a terminal and running the command: sudo parted -l (Lower Case Letter L in the command). You may need to post more information if you haven't resolved this issue. THe easiest way to do that with any of the Ubuntu derivatives is to use the boot repair software (link below), download it on the Kubuntu usb and use the 2nd option using the ppa and only use the Create BootInfo Summary option. After it runs, it will give you a link which you can post here and the information will be available for members here who may be able to suggest a solution. Without more details on your setup, all we are doing here is guessing.

https://help.ubuntu.com/community/Boot-Repair

1 members found this post helpful.

^ I agree with yancek's comments and recommendation.

as @ondoho stated supergrub is something I'd recommend having on hand, a dedicated 8GB Stick with supergrub burned to it. mine is red for easy recognition, and I was using it again just yesterday to fix some issues. it works with all OS, yes windows too.

so if your OS'es are installed, boot into your Linux reestablish grub, gurb-install and update-grub.

--> UEFI bios, MBR HDD : Your HDD got a be GPT Not MBR to use UEFI. FYI

so if your Win7 don't got UEFI then its over kill to even install Linux as UEFI, I'd keep it simple and consolidated as all MBR booting.

if all you have is OS'es installed, and no real loss in personal data, or a hit on personal data you can deal with, I'd go back and reinstall everything if you can. as some in here said Win7 don't got UEFI so as suggested before, turn off UEFI in your BIOS and go MBR that still works well with grub2.

GOAL: To install Win7 & Kubuntu, as a dual boot, on a older model desktop.
AMD FX8320 Socket AM3+
ASRock 970 Extreme3
16 GB DDR3
. . .
Used a DVD to install Win7 [success]
Used a USB drive to install Kubuntu [success] (*there is no mention or option to install as MBR or GPT)
After reboot,error message: Reboot and Select proper Boot device or Insert boot media in selected boot device and press a key - - -
SO I CANNOT "BOOT INTO LINUX" and run GRUB repair, etc.
. . .
Suggestions for installing a dual boot on SSD?
. . .
Assume that I am a total newbie and SPELL OUT each procedure. No arcane bafflegab, please.

Thank you for your help in this matter.

Basically repeating your intial post info isn't helpful. You've been asked several questions and told how to get detailed information on your system and you haven't done that. Without that info, nothing much anyone can do.

Check the post history of the OP.

After repeated errors*, even after using the boot loader repair tools, I resorted to wiping the HDD and installing Kubuntu by itself.
This time, no error message.
While examining the disk via KDE Partition manager, noted that there were two partitions : /dev/sda1 (fat32) for /boot/efi; and /dev/sda2 (ext4) for /.

(* error message: The 'grub-efi-amd64-signed' package failed to install into /target/. without the GRUB boot loader, the installed system will not boot.)

http://linuxbsdos.com/2017/08/29/sol...l-into-target/

https://askubuntu.com/questions/7899...llation-target

well i guess i can't help you then.

but what you want is definitely possible.
i'm sure you'll get there eventually.