Important: If September 2025 CU for SharePoint has been installed before, 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 Below […]
Important: If September 2025 CU for SharePoint has been installed before, 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 […]
Important: If September 2025 CU for SharePoint has been installed before, 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 […]
Important: If September 2025 CU for SharePoint has been installed before, 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 […]
The product group released the October 2025 Cumulative Update for Office Online Server. The KB article for October 2025 CU will be available at the following Location in a couple of hours: KB 5002797 – October 2025 Update for Office Online Server The download for October 2025 CU is available through the following link: Download […]
The product group released the October 2025 Cumulative Update for SharePoint Workflow Manager. The KB article for October 2025 CU will be available at the following Location in a couple of hours: KB 5002785 – October 2025 Update for SharePoint Workflow Manager The download for October 2025 CU is available through the following link: Download […]
Since multiple Trending Issues have now been documented for the September 2025 CU, and it’s becoming increasingly difficult for individuals to keep track, I’ve decided to create a single summary page. Issue Status SharePoint 2013 Workflows fail in combination with Classic Microsoft Workflow Manager after September 2025 CU Warning: Upgrade to SPWFM required before July […]
To enhance security the encryption algorithm used by the secure store service to save credentials has been update to a more secure version. As a side effect credentials stored with the old algorithm can no longer be decrypted. Symptoms When trying to edit an existing target application or when trying to add/update credentials the following […]
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 […]
