EFI partition too small, can't update Windows 11 on laptop

[Maxiaid]

I'm trying to update to Windows 11 24H2 on my ASUS laptop, but I'm greeted with the "We couldn't update the system reserved partition." message and error code 0xc1900201.
For what I've read online, this is because these laptops have hefty firmwares that clutter up the small EFI partition, which is 100MB by default.

23H2 works just fine, but I don't want to be left out of all future updates because of this, and I don't want to go through the hassle of formatting either.
I'm wondering, is it possible to update an existing OS from an installation media flash drive, and would that bypass this problem? Any more bright ideas?
Thanks in advance.

 

[_roman_]

Why not change the partition sizes?

I think you will find plenty of guides how to do a backup. how to change partition sizes. I assume you know your bitlocker key?

 

[agent_x007]

Short answer : It's a pain in the a**. Backup your files, reinstall Windows with proper partition sizes, and use recovery option from backup on new install to get your files back.

Longer answer :
Here's example of what you would have to do, to make this work without reinstall (view from Windows Disk Management) :

You need a partition manager that can create free space somewhere (usually easy part), AND enables you to move ALL partitions between this new free space and EFI partition (so that, free space created will be at the end of your EFI partition - as seen in Step #2).
Warning : Moving OS partition is usually only available in payed versions of 3-rd party partition managers.

Notes :
1) Windows doesn't allow "free movement" of partitions on non-dynamic drives.
2) Dynamic drive can be a boot OS drive for Windows 10/11, BUT that is NOT default when you install your OS - in 99% of cases you see non-dynamic Windows OS drive.
3) Windows Disk Management tool can't decrease partition size if there are files at the end of it (you have to remove/move those files to proceed with decrease in size). It also can't move partitions (of any type), on non-dynamic drives.
4) Free space from decreased partition size always shows up at the end (ie. on right side of it [marked on Step #1 from above screenshot], when viewed in Disk Management software).
5) Partition size can only be increased IF there is free disk space at the right side of it (as seen on Step #2).

 

[Flaky]

Simplier and less painful option to consider is to free up some space after any larger partition (as in agent's step #1) and just move the EFI partition there.
This should be doable using built-in tools, preferably from within winPE or winRE. Maybe 3rd party tools support this.
Optional step: suffer OCD from having un-allocated 100MB space where previous EFI partition used to be.

 

[Bill_Bright]

I'm trying to update to Windows 11 24H2

This is an old problem that surfaced big time a couple years ago. Seems odd you have not run into it before.

I recommend increasing the size to ~500Mb. See this: Windows 10/11 System Reserved Partition Is Too Small? [Fixed]

 

[INSTG8R]

This is an old problem that surfaced big time a couple years ago. Seems odd you have not run into it before.

I recommend increasing the size to ~500Mb. See this: Windows 10/11 System Reserved Partition Is Too Small? [Fixed]

This the solution. You may have to brush up on your DOS for it but it's not too complicated and doesn't mess with your current install
Edit looks like Bill has an even simpler solution I went through a whole DOS based procedure to safely extend the Recovery partiton to allow this update to install correctly

 

[STSMiner]

Google ...

Minitool Partition Wizard change size of partition....

 

[Maxiaid]

Why not change the partition sizes?

I think you will find plenty of guides how to do a backup. how to change partition sizes. I assume you know your bitlocker key?

I do know the Bitlocker key, but will the backup restore the whole OS to its current state? I've never really done any full system backups even though I know I probably should, I just try to upload important files to a cloud service every now and then. What I really don't want to deal with is setting up every single piece of software all over again just because Microsoft decided that my EFI partition had to be tiny.

Short answer : It's a pain in the a**. Backup your files, reinstall Windows with proper partition sizes, and use recovery option from backup on new install to get your files back.

Longer answer :
Here's example of what you would have to do, to make this work without reinstall (view from Windows Disk Management) :
View attachment 386234
You need a partition manager that can create free space somewhere (usually easy part), AND enables you to move ALL partitions between this new free space and EFI partition (so that, free space created will be at the end of your EFI partition - as seen in Step #2).
Warning : Moving OS partition is usually only available in payed versions of 3-rd party partition managers.

Notes :
1) Windows doesn't allow "free movement" of partitions on non-dynamic drives.
2) Dynamic drive can be a boot OS drive for Windows 10/11, BUT that is NOT default when you install your OS - in 99% of cases you see non-dynamic Windows OS drive.
3) Windows Disk Management tool can't decrease partition size if there are files at the end of it (you have to remove/move those files to proceed with decrease in size). It also can't move partitions (of any type), on non-dynamic drives.
4) Free space from decreased partition size always shows up at the end (ie. on right side of it [marked on Step #1 from above screenshot], when viewed in Disk Management software).
5) Partition size can only be increased IF there is free disk space at the right side of it (as seen on Step #2).

Wow, thanks for such a detailed guide!

Simplier and less painful option to consider is to free up some space after any larger partition (as in agent's step #1) and just move the EFI partition there.
This should be doable using built-in tools, preferably from within winPE or winRE. Maybe 3rd party tools support this.
Optional step: suffer OCD from having un-allocated 100MB space where previous EFI partition used to be.

Can I do that??? I don't care losing those 100MB to unallocated space. Any idea how can I achieve this using Windows' native tools?

This is an old problem that surfaced big time a couple years ago. Seems odd you have not run into it before.

I recommend increasing the size to ~500Mb. See this: Windows 10/11 System Reserved Partition Is Too Small? [Fixed]

I'll look into it. I read messing with partitions can be dicey, that's what scares me about these 3rd party methods, since I don't know how to back up my OS to begin with. Maybe I should start there.

I was able to update my desktop PC despite having an equally sized set of partitions, though. Can this cause any other issues beyond failed updates? I don't plan to use more than one OS, mind you.

 

[_roman_]

Nothing is for free

If you are worried I would consider cloning the disk to a new drive. In this process just change the partition sizes.
I would recommend making those partitions for future proof 1GB in size each. Bigger = most likely hassle free future

Data storage can fail anyway. So maybe a good point in time to buy a new drive + usb enclosure (usb bridge) + clone it. Clone the drive and swap it.

Is your problem related to this? https://support.microsoft.com/en-us...e-update-400faa27-9343-461c-ada9-24c8229763bf

 

[Bill_Bright]

I read messing with partitions can be dicey

It can be. But in reality, problems are very rare. And for sure, the 3rd party tool suggested has a solid reputation for not messing things up. Aomei Partition Assistant is another good, reliable program - and also free for home, non-commercial use.

Still, while slim, something could happen. A power failure right in the middle of the operation could be bad. So you should at the very least make sure you have a backup copy of your personal files, photos, ect. - which you should already have anyway.

 

[INSTG8R]

Nothing is for free

If you are worried I would consider cloning the disk to a new drive. In this process just change the partition sizes.
I would recommend making those partitions for future proof 1GB in size each. Bigger = most likely hassle free future

Data storage can fail anyway. So maybe a good point in time to buy a new drive + usb enclosure (usb bridge) + clone it. Clone the drive and swap it.

Is your problem related to this? https://support.microsoft.com/en-us...e-update-400faa27-9343-461c-ada9-24c8229763bf

Yeah that is the method I used. Because it's the Recovery Partition you can't just go willy nilly trying to allocate more space to it

 

[DirtyDingusMcgee]

Definitely back-up first (a clone is a great idea). If it were me, I'd probably de-crypt the drive and disable bitlocker first too.

Aomei, minitool, paragon (my current fave), Easeus, PartedMagic, etc. They all will do it just fine. Use their bootable media to boot to, as it is a much easier process with your windows offline.