After installing MX23.6 Windows is missing in the dual boot menu [Solved]

[FullScale4Me]

noursle,
This may be of value (or not). At times I've had to reinstall and the Windows menu has disappeared. What I have found success in is boot into MX. Grab from mxpi if you haven't already got it installed, Grub Customizer. Run GC and you very well may find (as I've done) the errant Windows menu. Good luck if the later suggestions in this thread don't solve your problem.

Grub Customizer can't customize what isn't there. Just sayin.

[noursle]

So, after 2 hours I gave it up to reinstall WIN ESP.
I followed the instructions I found on the internet, but I fail at the last step:
1) Boot with Win USB-Stick
2) Repair your Computer
3) Troubleshoot
4) Command prompt
5) diskpart
6) list disk
7) sel disk 1
list part
9) sel part 1 (Fat partition SYSTEM)
10) assign letter=y
11) exit
12) format y: /fs:FAT32
13) bcdboot c:\windows /s y: /f UEFI
and here I get the error message: "Failure when attempting to copy boot files."

I restarted my PC with the MX Boot-USB Stick and recreated with the MX-BOOT-Reparatur the MX-LINUX BOOT menu.
And here I am again...long live MX LINUX!!

[FullScale4Me]

...
13) bcdboot c:\windows /s y: /f UEFI
and here I get the error message: "Failure when attempting to copy boot files."

I restarted my PC with the MX Boot-USB Stick and recreated with the MX-BOOT-Reparatur the MX-LINUX BOOT menu.
And here I am again...long live MX LINUX!!

This means your choice of the drive letter C:\Windows was incorrect. Yes, it is the main drive letter when Windows boots normally.

What was likely not clear in the directions you were following as to how to identify the Windows main 'drive' for bcdboot.

Look for a volume of 48 Gb to 62 Gb in size (or more) as that will be it. BTW you don't have to use C as the drive letter, it can be any letter other than y and will work fine.

[DukeComposed]

This means your choice of the drive letter C:\Windows was incorrect.

What was likely not clear in the directions you were following as to how to identify the Windows main 'drive' for bcdboot.

The diskpart utility can be really beneficial here. Not only does diskpart have the power to perform the format action directly ("format fs=fat32 quick") but after assigning a letter to the EFI partition one can also list all volumes on the disk ("list volume" or "list vol"). This is an easy way to figure out where things are in a Windows rescue session and pinpoint where common drives like C:, D:, and X: ended up being put.

It can take a little guesswork if you've partitioned the disk in a unique way ("I want a 50 GB Windows partition and a 50 GB data partition on the same disk") and has to be done for every disk in the machine because diskpart only inspects one disk at a time, but for most users who follow Windows setup best practices, you'll only have one OS Disk and only a couple of partitions on it. Giving your Windows volumes sensible labels ahead of time can also help identify them later.

[noursle]

Dear all,

many thanks, I could reinstall a correct Windows-EFI Boot Partition after changing the letter to E: instead of C:.

I could find the correct partition name with the diskpart command: "list vol".
Then I have done an "exit" from the diskpart-tool, changed to E: and checked with "dir" if I could find the Windows directory.
And yes, there it was!
(y: is my empty boot partition, see step 10 from post #22)
Back to "X:\source" and then I entered the command: "bcdboot E:\windows /s y: /f UEFI"
and voilà, no error code and the EFI Boot Partition could be created.
I restarted my PC and I could boot to Windows (since end of january 2025).

After running the Windows updates, I made a Shortcut "Shutdown.bat" with the following code: "shutdown /s /t 0" and clicked on it.
Then I restarted my PC with the MX-Linux Boot stick, bootet my MX-Linux and opened a terminal and entered the following command:
"sudo update-grub"
Then I restarted my PC, clicking the F8-button (on my PC, on yours it could be F-12) to enter the UEFI bootmenu.
There I was able to select an entry to start WIN or MX-Linux.

I learned a lot of your all, many thanks!

This issue can now be closed.

[Eadwine Rose]

Please click the checkmark in the top right of the post (to the left of the username/user image) that holds the solution to mark the topic solved, thanks :)