“We couldn’t update system reserved partition” error installing Windows 11 24H2

[andreshko]

I have an HP laptop, which could not be updated to Windows 11 24H2. Setup failed with errors "We couldn’t update system reserved partition" and error codes 0x8007007f, 0xc1900201etc. at random % (after like 70%) of completion, and even automatic installation rollbacks after 100%.

Having absolutely useless crap like HP Diagnostics and HP BIOS update on a default sized 100 MB EFI partition makes any attempt to update Windows impossible. The EFI partition is 99.7% full, 47% of which is the mentioned HP useless crap. I am not going to express myself about it…

What did I do to have Windows 24H2 update successfully. Mounted the EFI partition (no matter what letter - e.g. mountvol y: /s). Moved y:\EFI\HP\BIOS\* to c:\EFI\HP\BIOS\* - there are 3 sub-folders named "Current", "New" and "Previous" with heavy load. Then freed up some more space deleting Windows boot fonts from y:\EFI\Microsoft\Boot\Fonts…

Happy end, no big deal…

[Sneha_01 · Accepted solution]

Hi @andreshko 

Welcome to HP Support Community.

Thank you for posting your query, I will be glad to help you.

It sounds like you successfully resolved the issue with the "We couldn’t update system reserved partition" error while installing Windows 11 24H2 on your HP laptop. Here’s a quick summary of the steps you took, which could help others facing a similar problem:

Steps to Resolve the "System Reserved Partition" Error

Check EFI Partition Size:

• The EFI partition was nearly full, which caused the installation failure.

Mount the EFI Partition:

• You used the command mountvol y: /s to access the EFI partition.

Move Files:

• You moved files from the y:\EFI\HP\BIOS\ directory to c:\EFI\HP\BIOS\, which included three sub-folders: "Current," "New," and "Previous."

Free Up Space:

• You deleted unnecessary files, such as Windows boot fonts from y:\EFI\Microsoft\Boot\Fonts, to create additional space.

Retry the Update:

• After freeing up space and moving files, you attempted the Windows 11 update again, which completed successfully.

Additional Tips

• Regularly Check EFI Partition: Keep an eye on the size of your EFI partition, especially after updates or installations.
• Backup Before Modifying: Always back up your data and critical files before making changes to system partitions.
• Consider Cleanup Tools: There are tools available that can help manage and clean up system partitions if you're not comfortable doing it manually.

I hope this helps.

Take care and have a good day.

Please mark this post as “Accepted Solution” if the issue is resolved and if you feel this reply was helpful click “Yes”.

Rachel571

HP Support

[Steviei]

Hi There all

I have the same issue. My query is how do I know how much of the EFI partition is in use.

When I look at the partitions in diskmgmt it just shows the EFI partition (Disk 0 partition 1) as 100Mb and healthy (EFI System Partition)

Thanks

[andreshko]

Open cmd and type:

mountvol y: /s

y:

dir

At the end you see your free space.

[Steviei]

Thanks very much for the info. Unfortunately my issue must be something else as the dir command says 0 used a nd 1 Dir(s) 9,526,272 bytes free

[andreshko]

9,526,272 bytes free is not enough space for the update.

I had to free up to above 50,000,000 bytes for the update to pass.

[Steviei]

Hi Again and many thanks Andreshko for your continuing support.

I dont understand why the dir command shows 0 files and 0 bytes

with 1 Dir (s) before the 9,526,272 bytes free. Shouldnt the sub directories and files be shown?

Also I dont understand why the update is not failing on all or most HP machines as they all have 100MB reserved partition with the HP stuff installed there. Why arent they all failing

[Steviei]

Finally remembered that of course you have to go in to the directories to see the files. Anyway deleted the fonts from the EFI\Microsoft\Boot\Fonts directory and all worked a treat and was able to install 24H2. It took an age.

Thanks again

[BigDusty]

Will deleting these font files on this drive cause other issues down the road?

[Steviei]

All I can say is that it hasnt caused any issues for me since