Need to resize System Reserved partition

garlin said:

WinPE Setup unfortunately hasn't done a good job when you ask it to wipe the disk (or use a blank drive), and default to 200MB in many instances.

It's like the Setup folks didn't really work with the EFI team. Same with the starting size of the Recovery partition... left hand of MS not talking to the right hand of MS.

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Yes, that is what I feel too. I wiped the laptop in 2023 and Setup created 100MB

Oh well, I now have 300MB, it should be good to go.

Thanks to all who provided good advice.

FWIW, I used MiniTool Partition Wizard to resize the EFI partition, it did so seamlessly. Obviously, it had to reboot to finish the job, but all was well.

gunrunnerjohn said:

FWIW, I used MiniTool Partition Wizard to resize the EFI partition, it did so seamlessly. Obviously, it had to reboot to finish the job, but all was well.

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I think the question most people want answered, is "Does it work from the free edition?"

garlin said:

I think the question most people want answered, is "Does it work from the free edition?"

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It works from the free edition.


I did mine yesterday... 100MB to 200MB... it needs to do it outside Windows ofc.
So after you apply, it has to reboot.

garlin said:

think the question most people want answered, is "Does it work from the free edition?"

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The Free edition boot disk is what I used and it worked great. I don't and have never messed with my working partitions online. (other than a simple extend or drive letter change) Old school? Maybe, but I'm old.

By the way, In my reading I found where Microsoft’s directive to OEMs suggests the EFI be from 260-300mb with 360 mb being optimum. Many OEMs have recently begun shipping systems with 300–500 MB EFI partitions to avoid upgrade failures. However, Microsoft still uses the legacy installer which creates 100mb EFI and they haven't announced if/when they plan to change it.

Until Microsoft changes their installer, I think it would be helpful if @Brink would include the diskpart commands in his clean install tutorial how to manually
clean install with a larger EFI partition. I know many of you scripting gurus can include these commands into your isos but most of us out here don't know how to do that.

There. I made it 500MB...





Maybe I should make it 5GB for Windows 27.

Ghot said:

There. I made it 500MB...

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That's 250MB that should have gone to Recovery!

glasskuter said:

Many OEMs have recently begun shipping systems with 300–500 MB EFI partitions to avoid upgrade failures.

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This Acer was reported new with a 512 MB EFI partition:

garlin said:

That's 250MB that should have gone to Recovery!

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I don't have or use a Recovery partition.

glasskuter said:

The Free edition boot disk is what I used and it worked great. I don't and have never messed with my working partitions online. (other than a simple extend or drive letter change) Old school? Maybe, but I'm old.

By the way, In my reading I found where Microsoft’s directive to OEMs suggests the EFI be from 260-300mb with 360 mb being optimum. Many OEMs have recently begun shipping systems with 300–500 MB EFI partitions to avoid upgrade failures. However, Microsoft still uses the legacy installer which creates 100mb EFI and they haven't announced if/when they plan to change it.

Until Microsoft changes their installer, I think it would be helpful if @Brink would include the diskpart commands in his clean install tutorial how to manually
clean install with a larger EFI partition. I know many of you scripting gurus can include these commands into your isos but most of us out here don't know how to do that.

Click to expand...

A clean install on the second PC here had a 200MB EFI partition, using Windows 11 26200.5074 ISO

Ghot said:

It works from the free edition.


I did mine yesterday... 100MB to 200MB... it needs to do it outside Windows ofc.
So after you apply, it has to reboot.

View attachment 152678

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Why is the EFI partition after the C: drive and not at the start? And will MiniTool still work if the partition is in the default place (start of the disk) ?

glasskuter said:

The Free edition boot disk is what I used and it worked great.

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Are we sure we are talking about the latest version downloadable from their website? The description clearly states that to run the "bootable version" you need at least the PRO version.

This was basically my question since the very beginning.

tony359 said:

Are we sure we are talking about the latest version downloadable from their website? The description clearly states that to run the "bootable version" you need at least the PRO version.

This was basically my question since the very beginning.

View attachment 152713

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Just grab the free portable version from their official website here. Besides being portable, the only difference is that it doesn't have an ad banner. It's straightforward in that It doesn't need extra stuff like the Windows Assessment and Deployment Kit (Windows ADK) and Windows PE add-on, and it also doesn't need a working Recovery (WinRE) partition.

When resizing a partition, you have a choice between moving the start of the partition or moving the end of the partition. The easiest way (IMO and IME) is to just change the unit size of the field from GB to MB before manually editing the value in the appropriate field.

BrianInEngland said:

A clean install on the second PC here had a 200MB EFI partition, using Windows 11 26200.5074 ISO

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Windows 11 25H2 installation media automatically creates a 200 MB EFI partition.

BrianInEngland said:

Why is the EFI partition after the C: drive and not at the start?

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Windows does not care which partition (or disk) the EFI partition is located on.

However, if the EFI partition is positioned between the Windows partition and the Recovery (WinRE) partition, Windows updates will not be able to expand the existing Recovery partition when it is too small.

The Windows RE update process makes every effort to reuse the existing Windows RE partition without any modification. However, in some rare situations where the new Windows RE image (along with the migrated/injected contents) does not fit in the existing Windows RE partition, the update process will behave as follows:

• If the existing Windows RE partition is located immediately after the Windows partition, the Windows partition will be shrunk and space will be added to the Windows RE partition. The new Windows RE image will be installed onto the expanded Windows RE partition.
• If the existing Windows RE partition is not located immediately after the Windows partition, the Windows partition will be shrunk and a new Windows RE partition will be created. The new Windows RE image will be installed onto this new Windows RE partition. The existing Windows RE partition will be orphaned.
• If the existing Windows RE partition cannot be reused and the Windows partition cannot successfully be shrunk, the new Windows RE image will be installed onto the Windows partition. The existing Windows RE partition will be orphaned.

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Right, so I tested that myself and I'm afraid my original question stands.

Yes, Minitool will restart and resize things - so that is a plus on AOMEI which will not.

HOWEVER, I've tested again on a different system and

- I could resize the main partition making free space to the left
- Minitool would NOT allow me to move that unallocated space close to the EFI partition
- I then rebooted, I thought the unallocated space had to be actually there
- Once rebooted I had my 100MB extra unallocated space between the 16MB and the main partition but I cannot move anything so I am unable to re-size the EFI partition as the unallocated space is not adjacent to it.

Ghot already stated they don't have the 16MB partition so that would work in that scenario.

GParted allowed me to move the 16MB partition so it was on the RIGHT of the unallocated space, making the unallocated space to the RIGHT of the EFI partition.

So, once again, how would you overcome this? See screenshots, there is no "move/resize" available on either the 16MB nor the unallocated space.

BrianInEngland said:

Why is the EFI partition after the C: drive and not at the start? And will MiniTool still work if the partition is in the default place (start of the disk) ?

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1. On Win 10 my disk was MBR
2. I did an In-Place Upgrade from Win 10 to Win 11, after using MBR2GPT
3. I think I moved it there on purpose. OCD reasons.
4. Yes. I just took a few hundred MB from the D: partition, and then resized the EFI partition.

If the EFI partition is in front of C:... just take a few hundred MB from C: and add it to the EFI partition.
Keep in mind that I remove the 16MB System Reserve partition, long ago. I removed the Recovery partition also.
I use 3rd party backup software.

garlin said:

I think the question most people want answered, is "Does it work from the free edition?"

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I'm using the free edition.

In the first posts of this thread there's some confusion for the following reason:


(*): (PS I see a more complete explain of the following in post #38) MBR can protect info (given sectors numbers PS "hidden sectors") from being overwritten regardless of if they're inside partitions, in gaps among partitions (the typical 1 MB gap and typical leading/trailing gaps), or in "big" unallocated spaces. I mean sector numbers used for some special purpose. The most clear example is the boot sector that must be in sector 0 (the first partition can include this sector, but it won't allocate foobar.txt there), but Windows, MS apps or 3rd party apps could use others. GPT drops these special sectors, in GPT there can only exist partitions inside the disks and files/filesystems metadata inside the partitions. The MSR partition was created to host these infos and allow compatibility with old utilities that use them. I have noticed or seen somewhere it's a strange kind of partition, with sub-partitions inside or similar, what matches its purpose of collecting unrelated infos in one place.

They chose a bad name for this new partition. What you were needing to enlarge is the... hmmmmmmm... how do I call this? How does documentation call this? Typically ESP or EFI partition, but in some case it could be called "System Reserved" as a legacy from MBR.

I would always keep the MSR (I admit it's technically easier to delete it, but it's just an additional step in the typical partition manager) unless you need 16 MB desperately, what is unlikely. That amount is so small that I wouldn't even trust it as additional EFI/ESP space. If Lenovo uses the normal 100 MB, I'd put another 100 MB at least for Windows.

In the 2nd page, I think problems might arise (or not) if something expects the MSR to be there and it's not. I haven't experienced it (I've never had to fiddle with my only GPT disk in my Win11 computer) but I see it plausible. Provided there isn't any old class, method, library,... still in use and using hidden sectors in MBR disks and the MSR partition in GPT disks. Or an old game etc.

tony359 said:

Right, so I tested that myself and I'm afraid my original question stands.

Yes, Minitool will restart and resize things - so that is a plus on AOMEI which will not.

HOWEVER, I've tested again on a different system and

- I could resize the main partition making free space to the left
- Minitool would NOT allow me to move that unallocated space close to the EFI partition
- I then rebooted, I thought the unallocated space had to be actually there
- Once rebooted I had my 100MB extra unallocated space between the 16MB and the main partition but I cannot move anything so I am unable to re-size the EFI partition as the unallocated space is not adjacent to it.

Ghot already stated they don't have the 16MB partition so that would work in that scenario.

GParted allowed me to move the 16MB partition so it was on the RIGHT of the unallocated space, making the unallocated space to the RIGHT of the EFI partition.

So, once again, how would you overcome this? See screenshots, there is no "move/resize" available on either the 16MB nor the unallocated space.

Click to expand...

Resize the MSR by:

1. moving the end of the MSR to the end of the unallocated space that comes directly after it, and
2. moving the start of the MSR such that the MSR will be 16MB in size (128MB is the recommended size for the MSR, though...)

The unallocated space will now be to the left of the MSR so, next, you will be able to extend the EFI by moving the end of the EFI to the end of the unallocated space that, now, comes directly after it.

It can be a bit of a sliding puzzle at times but it gets the job done nicely (at least if you don't have to do this multiple times per day).

P.S., normally, the default size of 100MB for the EFI is perfectly fine so you don't normally need to make it bigger unless you really need to (e.g., to set up some kind of advanced multiboot configuration).

MSR is the 16MB one, right? If so, I don't have a Move/Resize option for that partition - see the attached in my previous post.