To enhance security a new Exploit Protection Setting was added to Windows when installing September 2025 CU. This adds several protections to OWSTIMER.EXE including an option that prevents creating child processes. SharePoint 2010 workflows require the workflow definition to be compiled using the CSC.EXE compiler – and this fails due to this Exploit Protection setting. […]
To enhance security a new Exploit Protection Setting was added to Windows when installing September 2025 CU. This setting works as expected on Windows Server 2022 but causes the SharePoint Administration Service to fail on Windows Server 2025. Symptom When running the SharePoint Configuration Wizard for SharePoint Server Subscription Edition on Windows Server 2025 fails […]
Several customers have reported issues when deploying custom solutions after installing the September 2025 CU for SharePoint Server 2016, 2019, and Subscription Edition. The following error is returned when deploying the solution: Cause The cause of this issue is a combination of new permissions assigned to the WSS_WPG and IIS_IUSRS Windows security groups — intended […]
After installation of September 2025 CU for SharePoint Server 2016, 2019 and Subscription Edition customers might notice a Health Analyzer entry similar to this: Cause September 2025 CU for SharePoint added a deny ACL to the _LAYOUTS directory of SharePoint in the 16 and 14 hive to prevent write access to this folder from accounts […]
Information: The issue described in this article currently affects only customers which executed the SharePoint Configuration Wizard after installing the language independent fix from September 2025 CU and the installation of the language dependent fix.Starting with October 2025 CU for SharePoint Server (all versions) most customers might be affected by this problem – so addressing […]
SharePoint Server 2025 CU for SharePoint Server 2016, 2019 and Subscription Edition includes security hardening for SharePoint Server 2013 workflows which enforces the most recent SharePoint Workflow Manager updates to be installed on SPWFM. As a side effect this also prevents classic workflow manager workflows from running as this version does not comply with this […]
I have received several reports from users that after installing September 2025 CU for SharePoint Server 2016, 2019 or Subscription Edition the SharePoint configuration wizard failed with the following error message: System.InvalidOperationException was thrown. Additional exception information: An internal error occurred. The program cannot continue to run. The program stopped because of the following: Copy […]
[Update from August 22nd – additional assemblies added] SharePoint Workflow Manager August 2025 CU switched from using the System.Data.SqlClient database connectivity layer to the modern and more powerful Microsoft.Data.SqlClient database connectivity layer. Microsoft.Data.SqlClient has different dependencies which are not automatically fulfilled on machines which do not have SharePoint Server Subscription Edition installed. Error messages similar […]
After installing the March 2025 CU (or any subsequent update) for SharePoint Server Subscription Edition, certain search administration pages include incorrect ASP.NET tags leading to the following or similar error message: An error occurred during the processing of /_admin/search/listmanagedproperties.aspx. The server tag is not well formed. System.Web.HttpException (0x80004005): The server tag is not well formed. […]
As a lot of readers of my blog mentioned in comments: KB 5002692 from April 2025 CU for SharePoint Server 2016 does not install. An incorrectly signed DLL is causing problems. My colleague Adam Sorensen has created a blog post on this topic: Blog Post: SharePoint 2016 – April 2025 KB 5002692 fails to install […]
After installing the March 2025 CU (or any subsequent update) for SharePoint Server Subscription Edition, certain search administration pages include incorrect ASP.NET tags leading to the following or similar error message: An error occurred during the processing of /_admin/search/listmanagedproperties.aspx. The server tag is not well formed. System.Web.HttpException (0x80004005): The server tag is not well formed. […]
After installing the October 2024 Cumulative Update (or any subsequent update) for SharePoint Server Subscription Edition, the Date column values in lists may incorrectly display as December 30th, 1899, instead of the correct date, under the following conditions: The site locale uses a date format where the day precedes the month (e.g., DD.MM.YYYY or DD/MM/YYYY). […]
