Our DBAs kept seeing error messages in their SQL Server log as follows: Login failed for user 'DOMAIN\SERVER$'. Reason: Could not find a login matching the name provided. [CLIENT: xx.255.222.22] There was an entry for almost all of the SharePoint servers in the farm. It seemed to occur three times per day at the same times: 5:32am, 1:32pm, and 9:32pm. I looked in the Event Viewer of one of the servers and located the error there too: SQL database login for 'SPS_SharePointConfig' on instance 'SPSQLSERVER' failed. Additional error information from SQL Server is included below. Login failed for user 'DOMAIN\SERVER$'. Using the Correlation ID in the Event Viewer item , I searched through the ULS Logs. I found several items in the SharePoint ULS logs: SQL database login for 'SPS_SharePointConfig' on instance 'SPSQLSERVER' failed. powershell (0x03AC) 0x1324 SharePoint Foundation Upgrade SPUpgradeSession ajxme ERROR CanUpgrade [SPConfigur...