HELP!!! Unable to boot win after efi partition resizing

Sucks to read this...I was in the same predicament about two months ago. My wife's HP laptop had an important BIOS update (I believe the main thing was starting the process of adding 2023 Secure Boot certs). I couldn't install it because the default EFI partition was too small...already consumed with Microsoft and prior HP BIOS files. My first attempt to resize it ended in this same situation. I tried Minitool, from within Windows, to 1) reduce Windows partition, 2) move the new unallocated space adjacent to EFI partition and 3) resize EFI partition. I can't remember the error I got but it failed and rendered the machine unbootable. Fortunately, I backed up the drive prior to playing around with the EFI, and was back up and running in about 20 minutes. After researching online I decided to try again another way. I downloaded and created a Gparted bootable disk. If I recall it couldn't complete all three actions at the same time. I think I had to do the Windows partition reduction and movement. When that successfully completed, I rebooted the machine and then did the EFI merge. It worked and I was able to update the BIOS immediately after.

Reviewing the thread I saw the OP's disk had/has the 600 MB unallocated space after C: (shrinking C: had been done with Diskmgmt, that cannot move partitions), not before like it could have been optimal. Anyway the total "effort" or "stress" might have been the same b/c sometimes partitioning tools move the whole partition data or the most of it they can when you move the partition, instead of using the free space for just the data that must be moved and update the file tables etc accordingly, what's a lot faster and less stressful. But at least the total task would have been distributed in two steps. That's why Easeus had to perform 3 tasks (move C:, move MSR and enlarge ESP/EFI).

I have under doubt that the ESP (or its MBR equivalent in Windows disks, the System Reserved partition) can be just extended with a 3rd party tool or via Diskmgmt if you happen to have contiguous unallocated space, or if you have just created it. A week ago I did that to a Windows 10 MBR disk trying to get that MBR2GPT would recycle the System Reserved as ESP. The conversion was basically successful but MBR2GPT treated my enlarged SR as any data partition, and it created the ESP at the end of C: with space shrunk from it (all these small issues are already fixed).

@nightf0x

I am closing down for the day and will be online only my tomorrow morning that is after another 10 hours. My time now is 20:57. and the NewYear starts in another 3 hours. Will see you tomorrow..

mccmw said:

Sucks to read this...I was in the same predicament about two months ago. My wife's HP laptop had an important BIOS update (I believe the main thing was starting the process of adding 2023 Secure Boot certs). I couldn't install it because the default EFI partition was too small...already consumed with Microsoft and prior HP BIOS files. My first attempt to resize it ended in this same situation. I tried Minitool, from within Windows, to 1) reduce Windows partition, 2) move the new unallocated space adjacent to EFI partition and 3) resize EFI partition. I can't remember the error I got but it failed and rendered the machine unbootable. Fortunately, I backed up the drive prior to playing around with the EFI, and was back up and running in about 20 minutes. After researching online I decided to try again another way. I downloaded and created a Gparted bootable disk. If I recall it couldn't complete all three actions at the same time. I think I had to do the Windows partition reduction and movement. When that successfully completed, I rebooted the machine and then did the EFI merge. It worked and I was able to update the BIOS immediately after.

Click to expand...

Thats nearly the same what happened to me but i didnt backup sadly, my mistake i didnt give any attention that it wont go through this process smoothly

jumanji said:

@nightf0x

I am closing down for the day and will be online only my tomorrow morning that is after another 10 hours. My time now is 20:57. and the NewYear starts in anothr3hours. Will see you tomorrow..

Click to expand...

Thanks sir @jumanji for your assistance & happy new year, the laptop has been out of service for a week now but i have to format it atlast as i need it for work

nightf0x said:

Thats nearly the same what happened to me but i didnt backup sadly, my mistake i didnt give any attention that it wont go through this process smoothly

Click to expand...

Admittedly, after I got my wife's EFI partition increased and BIOS updated, I had no issues doing the same to my laptop and desktop computers. The hardest part in using Gparted takes a very long time on a large drive. Once it creates the unallocated space at the front of C: drive, it takes very long to move everything else so it can move it adjacent to the EFI partition.

nightf0x said:

Thanks sir @jumanji for your assistance & happy new year, the laptop has been out of service for a week now but i have to format it atlast as i need it for work

Click to expand...

OK, after formatting, Install Windows. WinRE environment > Troubleshoot > Reset > Remove everything > Cloud download will be the best thing to do.
When you perform a full PC reset in Windows, especially the "Remove everything" option, the Trusted Platform Module (TPM) is typically cleared as part of the process to ensure all security data, like encryption keys for BitLocker or Windows Hello, is wiped clean for a fresh start
Keep us posted.

If possible, for academic purposes before the planned format > clean install please attempt a custom install > post error messages and codes