Fix “Access Denied” on Registry and Filesystem

Today I installed the May CU on a SharePoint 2013 farm hosted in Azure. After the Installation was done (with a PowerShell script that disables some services to speed up the process), there were Exceptions opening the User Profile Service (UPS) settings page.

So I investigated the logs and found many entries about “Access Denied”. Some directly pointed to the registry hive “HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office Server\15.0” with the message Requested registry access is not allowed. or Getting Error Message for Exception System.Security.SecurityException: Requested registry access is not allowed., others about access to directories Access to the path ‘C:\Program Files\Microsoft Office Servers\15.0\Data\Office Server\CanonicalResources\ProjectionModels\EN_EN.mdl’ is denied.

Well, the short answer to fix the problem is: You need to execute the SharePoint Configuration Wizard on each server of the farm after installing an update.