Error 0x800f0922 for 2020-01 Cumulative Update for Windows 10 Version 1909 for x64-based Systems (KB4532695)

I thought others might benefit from my experience. The problem was solved but it was rather strange.

I tried to install Windows from an ISO image created by the Windows media creation tool. It didn't work. Eventually I figured out it was not seeing enough free space for temporary files, but my C: drive has more than 500GB free.

I went into DISKPART and after much rooting around discovered that the GUI ID for my EFI System partition was wrong. I'm guessing this happened when I expanded it to 500MB from 100MB as per  HiltonOishi's suggestion in https://answers.microsoft.com/en-us/windows/forum/all/failed-install-attempt-error-code-0x800f0922/c5eb31d7-f04f-4ff8-9d6f-f39e4f03944b.

I set the EFI partition's GUID to c12a7328-f81f-11d2-ba4b-00a0c93ec93b as it should be and retried the Windows installation from ISO. This time it seemed it would continue, so I interrupted it and ran the update I had been trying to install, and it installed without a problem.

Thanks for posting that, very helpful.  Same thing happened to me after cloning my system to a larger drive.  FYI, for others to steps to fix this involve using diskpart, selecting the correct partition and then running this command.  "set id=c12a7328-f81f-11d2-ba4b-00a0c93ec93b override"

But what if the ssd disk is MBR?

I thought others might benefit from my experience. The problem was solved but it was rather strange.

I tried to install Windows from an ISO image created by the Windows media creation tool. It didn't work. Eventually I figured out it was not seeing enough free space for temporary files, but my C: drive has more than 500GB free.

I went into DISKPART and after much rooting around discovered that the GUI ID for my EFI System partition was wrong. I'm guessing this happened when I expanded it to 500MB from 100MB as per  HiltonOishi's suggestion in https://answers.microsoft.com/en-us/windows/forum/all/failed-install-attempt-error-code-0x800f0922/c5eb31d7-f04f-4ff8-9d6f-f39e4f03944b.

I set the EFI partition's GUID to c12a7328-f81f-11d2-ba4b-00a0c93ec93b as it should be and retried the Windows installation from ISO. This time it seemed it would continue, so I interrupted it and ran the update I had been trying to install, and it installed without a problem.

Thanks for posting that, very helpful.  Same thing happened to me after cloning my system to a larger drive.  FYI, for others to steps to fix this involve using diskpart, selecting the correct partition and then running this command.  "set id=c12a7328-f81f-11d2-ba4b-00a0c93ec93b override"

(1) HarddiskVolume1 is the 1st partition on Disk 0. It begins counting with the partitions on Disk 0 & progresses to the other disks, if any.

(2) HarddiskVolume3 is your 3rd partition on Disk 0. It is your Windows partition. ReagentC shows it also contains your Recovery Environment (to which Shift+Restart will boot). Normally, that would be in a partition of its own, but I suppose Bootcamp wanted it this way. It could happen this way in other circumstances as well. When I briefly dual-booted, the second Windows installation was like that. (The first kept its existing Recovery partition to itself.) It updated OK, so I doubt that's the problem.

(3) I suppose that unknown partition 2 of 91 GB is your wife's "MBA" which I suppose is Apple's OS. I don't know why it intercedes between EFI & Windows. Doesn't seem right, but I know nothing about it.

(4) You are right, the issue for you is not that EFI has a wrong type ID. That's the right one. Normally, the size of EFI these days is 100 MB, but 300 MB is OK too. Maybe Bootcamp wants it that way, I don't know. But I would give it GPT attributes that looks like helzayat's & mine this way...

https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/gpt

GPT

At an Administrator Command Prompt, enter these commands...

DiskPart

Select  Disk  0

Select  Part  1

GPT  Attributes **=**0x8000000000000000

Detail  Part

Exit

But it just doesn't sound like that is a solution to the update failure. Also, I don't know whether Bootcamp wants it that way.

(5) What I like least is that you are missing the MSR (Microsoft Reserved) partition. These days it is 16 MB & located just before the Windows partition, if Windows creates it during a clean install. It used to be 128 MB. All GPT disks are supposed to have one...

DISKPART> Select Disk 0

Disk 0 is now the selected disk.

DISKPART> List Part

Partition ###  Type              Size     Offset

  -------------  -------------  -------    -------

  Partition 1    System          99 MB    32 KB

  Partition 2    Reserved       16 MB   100 MB              <<< MSR partition

  Partition 3    Primary        930 GB   116 MB

  Partition 4    Recovery      790 MB   930 GB

DISKPART> Select Part 2

Partition 2 is now the selected partition.

DISKPART> Detail Part

Partition 2

Type    : e3c9e316-0b5c-4db8-817d-f92df00215ae

Hidden  : Yes

Required: No

Attrib  : 0X8000000000000000

Offset in Bytes: 104889856

There is no volume associated with this partition.

DISKPART>

(6) Do you have other disks & does any have another EFI partition on it? That could confuse Windows during a reboot to complete the installation of an update.

I assume you're talking about a Mac Book Air? I have almost zero experience with Macs and none at all with Boot Camp. Sorry.

For what it's worth, the only thing that looks different in what you show from what I have is that in my case the EFI partition shows attrib 0X8000000000000000 (and I have a differently sized EFI partition).

Glad that worked out.

Hello helzayat,

Thank you so much for taking the time to help out.  I am trying to fix my wife's MBA which has Bootcamp and she is likewise encountering this "Error 0x800f0922" message every time she tries to install the latest "2020-04 Cumulative Update for Windows 10... 1090... (KB4549951)" I suspect the problem is what you've described here on this thread.  I've read through all of the messages and just have one question--

Here is what her boot manager looks like:

And here's what her diskpart looks like:

I notice that the Windows Boot Manager thinks that "HarddiskVolume1" is the "device" that it should be looking at.  But does it know to correctly look on "Disk 0"  ?

(Note that EFI Partition 1 is indeed the **"**c12a7328-f81f-11d2-ba4b-00a0c93ec93b" GUID so I don't think that's my specific issue like it was the previous poster's.)

Thank you so much for helping everyone!  You're a generous soul!