Important: If your current farm patch level is September 2025 CU, remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint machines – otherwise installing the SharePoint fixes will fail.
For more details check this article: Trending Issue: SharePoint fixes fail to install after installation of September 2025 CU
The product group released the December 2025 Cumulative Update for SharePoint Server Subscription Edition.
Monthly SharePoint Server Subscription edition updates are released as a single unified “uber” package containing both the language independent and language dependent fixes. Language independent and language dependent fixes will no longer be released separately. This is similar to the full server packages released for SharePoint 2013.
The KB article for December 2025 CU will be available at the following location in a couple of hours:
- KB 5002815 – December 2025 Update for SharePoint Server Subscription Edition
This is also a security update!
The download for December 2025 CU is available through the following link:
It is irrelevant which language you pick on the drop down in download center. It will always download the same package.
After installing the fix you need to run the SharePoint Products Configuration Wizard on each machine in the farm. If you prefer to run the command line version psconfig.exe ensure to have a look here for the correct options.
Please ensure to have a look at the SharePoint Patching Best Practices before applying new fixes.
SharePoint Server Subscription Edition December 2025 CU Build Number: 16.0.19127.20378
Important: To minimize the installation time for SharePoint Server Subscription Edition Fixes, please follow the guidance in the following article: Solving the extended install time for SPSE CUs
Related Links:
- Learn: 25H1 Feature Update for SharePoint Server Subscription Edition
- Learn: Updated Product Servicing Policy for SharePoint Server Subscription Edition
- Learn: FAQs for SharePoint Server Subscription Edition product servicing policy
- Blog: SharePoint Patching Best Practices
- Blog: SharePoint Patching demystified
- Blog: Why I prefer PSCONFIGUI.EXE over PSCONFIG.EXE
- Technet: Update Center for Microsoft Office, Office Servers, and Related Products
- Blog: SharePoint Server 2016 Zero-Downtime Patching Demystified (applies also to SharePoint Server 2019)
- Blog: SharePoint does not have a build version. Full Stop.
- Blog: Solving the extended install time for SPSE CUs
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Hi Stefan,
As I requested last month, do we have any update regarding the active issues posted against SPSE version in the below blog ?
https://blog.stefan-gossner.com/2025/09/25/summary-and-status-of-issues-identified-with-september-2025-cu-for-sharepoint/
Thanks,
Karthikeyan P
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Hi Karthikeyan,
there is no update available. All the yellow issues are still under investigation or in work.
Cheers,
Stefan
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Just a recommendation, when an update to the SharePoint Workflow Manager is needed BEFORE the CU is applied it would be most helpful for that to be called out in the posting like the remove of the id’s has been. This is the second CU that we got bit with installing, having workflow issues and digging in found the details in the KB article…. yes, should have read that first but this was never a norm before, so it is a new habit we need to get into.
Is it now going to be a standard moving forward that the most recent SharePoint Workflow Manager CU must be installed prior to the SharePoint CU?
If you’re currently running SharePoint Workflow Manager, you must install SharePoint Workflow Manager (KB5002799) to your farm before you install this cumulative update.
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Thank you Lee for noting this.
Stefan, is the stapling of SPWFM updates to SharePoint CUs going to be a standard practice going forward, or were the August/September and November/December situations one-offs?
Thank you – Chad
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Hi Chad – no this is not standard practice.
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Hi Stefan,
to come back to the topic of the AppPool crash in SPSE w3wp.exe with Exception code = 0xC0000409: Is there anything new about this yet?
Will it be fixed in a CU or will there be a separate patch?”
br chris
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Hi Chis,
this is still under investigation.
Cheers,
Stefan
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I usually encounter the issue
Failed to upgrade SharePoint Products.
An exception of type Microsoft.SharePoint.PostSetupConfiguration.PostSetupConfigurationTaskException was thrown. Additional exception information: The upgrade command is invalid or a failure has been encountered.
Upgrade [SearchAdminDatabase Name=….] failed
Exception: User does not have permission to perform this action.
Do you have any articles to resolve this issue?
Thanks
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Hi Quan,
as the error is related to DB permissions I would involve some SQL experts on your side which monitor the system to see wich objects are causing this.
Cheers,
Stefan
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Hi Stefan,
After applying the patch this month, the custom timer job deployed by WSP had disappeared. I couldn’t also find the features for activation.
Do you know the reason?
Thanks
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Hi Quan,
I haven’t heard about such a problem. Did you retract and reactivate the solution? Does the timerjob come back after this?
Cheers,
Stefan
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Hi Stefan,
Greetings of the day!
We are observing a significant number of errors across our SE farm, and I wanted to share the details for your analysis.
SE Farm – Application Crash Details
We are seeing repeated crashes with the following event information.
Faulting application: w3wp.exe
Version: 10.0.20348.1
Time stamp: 0x405e4c14
Faulting module: KERNELBASE.dll
Version: 10.0.20348.4294
Time stamp: 0x73e9e45d
Exception code: 0xe0434352
Fault offset: 0x000000000003f33c
Process ID: 0x4138
Application start time: 0x01dc70aef772ee33
Application path: c:\windows\system32\inetsrv\w3wp.exe
Module path: C:\Windows\System32\KERNELBASE.dll
Report ID: 1f192365-12bc-4171-b0d1-a6dc4b563f55
No package information was included in the event.
Workflow Servers – Errors After November Workflow Updates
After installing the November Workflow updates, we are seeing the following crash reports.
Fault bucket: type 0
Event name: CLR20r3
Response: Not available
Cab ID: 0
Problem signature:
P1: PFCDMJFWRPUBG02IPZLOVDATHMCRILJG
P2: 16.0.19127.20336
P3: a15a08b1
P4: Microsoft.Cloud.ServiceBus.Client
P5: 16.0.19127.20336
P6: fedfdd6e
P7: 3338
P8: 1f
P9: D5FQXEG2XSDL53CIYROAU411MHRNEMUK
Attached files:
Located under:
\?\C:\ProgramData\Microsoft\Windows\WER\Temp\xxx
Additional reports may be available here:
\?\C:\ProgramData\Microsoft\Windows\WER\ReportQueue\AppCrash_xxxxx
Report ID: d93e939e-3141-4d9e-ab8d-6f123dc6cbc4
Report status: 4196
Please let us know if you need any additional logs, dumps, or traces to help with the investigation
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Hi Chandu,
the SPSE one is a known issue:
https://blog.stefan-gossner.com/2025/12/19/trending-issue-sharepoint-worker-process-crashes-with-0xc06d007e-and-0xe0434352-exceptions/
I haven’t seen the SPWFM. For this I would suggest to open a support case with Microsoft.
Cheers,
Stefan
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Might be useful to add a reference for the 2 new Articles in September summary of issue article. Might save someone.
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Hi Joseph,
the C0000409 was indeed introduced with September 2025 CU.
But the issue with C06D007E and E0434352 was already reported for July 2025 CU.
The problem exists in the code already since RTM – but as this is a race condition between http requests the frequency of the issue has changed over time due to other code changes changing the timing of the executed http requests.
Cheers,
Stefan