I'm not sure what happened but few hours after the update, I could no longer boot the laptop. The displayed message is "reboot and select proper boot device". I am able to enter setup and confirm it is UEFI boot and the hard disk is listed. I am also able to boot from USB and run Kyhi's rescue disk listed elsewhere in this forum. Not sure how to fix this. Your suggestions are appreciated. Here is an image of my disk partitions:
On Kyhi's Recovery Drive is Macrium Reflect. Run Macrium Reflect and on the restore menu is a utility to Fix Winodws boot problems. Run that utility.
You probably did not boot Kyhi's Recovery Drive in UEFI mode. On the boot menu you should see the USB flash drive listed twice, make sure to select the entry that has UEFI in front of it.
You can delete the existing EFI System partition and create a new one manually. From your screenshot, delete 100 MB FAT32 partition using the partition assistant program. It will warn you about deleting the system partition and the computer not booting, just accept the warning. Then open a command prompt and run the following commands:
diskpart
select disk 0
create part efi
format fs=fat32 quick
assign letter=t
exit
bcdboot C:\Windows /s T: /f ALL
exit
I don't see an option on boot menu for seeing that USB drive twice. But when I run Macrium Reflect it indicates [UEFI] at the end of the title bar so perhaps it's running in UEFI mode?
I went ahead and deleted the EFI partition, then 'applied' the changes in partition assistant program. I then open a command prompt and started the sequence you listed. When I get to the "format fs=fat32 quick" (also tried all uppercase letters), it indicates "DiskPart has encountered an error: The parameter is incorrect. See the system Event Log for more info." I don't know where that log might be. Another piece of data, the type of filesystem is noted as RAW when I view it in diskpart using "list vol". This was also the case even before I deleted the partition. As seen from my initial post it is listed at FAT32 when using the partition assistant program.
K. Try deleting the same partition in partition assistant. Then command prompt. Then:
diskpart
select disk 0
create part pri
format fs=fat32 quick
assign letter=t
exit
bcdboot C:\Windows /s T: /f ALL
exit
The difference is in the create part command.
I got the exact same failure at the "format fs=fat32 quick" step.
I noticed partition assistant had a format command so I tried that command with parameters FAT32 and default size of 1024 and it seemed to work. I then proceeded with your additional commands making sure I selected disk 0 and the correct volume in diskpart . I made progress, I attempted to boot from my hard disk and now see the windows spinning dots for long time ( 20-30minutes). When it finally finished I get a blue screen with a stop code: Bad system configuration info. Tried to boot again and got a blue screen with error code : c0000001. When I look at the disk partition info again, I do not see that recreated FAT32 partition marked as EFI, it only has the GPT flag set. Should I be concerned? I did try the Macrium fix boot command again and results are still the same ie "no active partition".
Go back into diskpart and select the fat32 volume. Then:
set id=c12a7328-f81f-11d2-ba4b-00a0c93ec93b
That will flag the fat32 partition as an EFI system partition. It's starting to sound like the Windows installation itself is corrupted, though, and you are probably looking at backing up the data you want to save and doing a clean install.
On a UEFI computer system, there is no active partition. And the disk should be partitioned as GPT, which is impossible to mark a partition as active on.
Thanks NavyLCDR . That id set the EFI flag. I did try further attempts to recover using dism but finally gave up and did a clean install. Appreciate your time and all your help.
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