We have received multiple reports indicating that SharePoint 2010–style workflows are failing after installing the June 2026 Cumulative Update (CU). Symptoms The issue is typically reflected in the ULS logs with entries similar to the following: w3wp.exe (0xXXXX)   SharePoint Foundation   Legacy Workflow Infrastructure   4letu   High   Block the namespace: clr-namespace:System.CodeDom;Assembly=System, Version=4.0.0.0, […]

Important: If your current farm patch level is September 2025 CU, execute the following PowerShell script to correct the folder permissions on the relevant folders otherwise installing the SharePoint fixes will fail: Fix-SeptemberCU-Permission-Problem.ps1 Alternatively you can also remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint machines. For more […]

Important: If your current farm patch level is September 2025 CU, execute the following PowerShell script to correct the folder permissions on the relevant folders otherwise installing the SharePoint fixes will fail: Fix-SeptemberCU-Permission-Problem.ps1 Alternatively you can also remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint machines. For more […]

Important: If your current farm patch level is September 2025 CU, execute the following PowerShell script to correct the folder permissions on the relevant folders otherwise installing the SharePoint fixes will fail: Fix-SeptemberCU-Permission-Problem.ps1 Alternatively you can also remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint machines. For more […]

Important: If your current farm patch level is September 2025 CU, execute the following PowerShell script to correct the folder permissions on the relevant folders otherwise installing the SharePoint fixes will fail: Fix-SeptemberCU-Permission-Problem.ps1 Alternatively you can also remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint machines. For more […]

Important: If your current farm patch level is September 2025 CU, execute the following PowerShell script to correct the folder permissions on the relevant folders otherwise installing the SharePoint fixes will fail: Fix-SeptemberCU-Permission-Problem.ps1 Alternatively you can also remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint machines. For more […]

Important: If your current farm patch level is September 2025 CU, execute the following PowerShell script to correct the folder permissions on the relevant folders otherwise installing the SharePoint fixes will fail: Fix-SeptemberCU-Permission-Problem.ps1 Alternatively you can also remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint machines. For more […]

Important: If your current farm patch level is September 2025 CU, execute the following PowerShell script to correct the folder permissions on the relevant folders otherwise installing the SharePoint fixes will fail: Fix-SeptemberCU-Permission-Problem.ps1 Alternatively you can also remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint machines. For more […]

Important: If your current farm patch level is September 2025 CU, execute the following PowerShell script to correct the folder permissions on the relevant folders otherwise installing the SharePoint fixes will fail: Fix-SeptemberCU-Permission-Problem.ps1 Alternatively you can also remove the NT Authority\system account from WSS_WPG and IIS_IUSRS local security groups of the SharePoint machines. For more […]