Cause: There is some system protection preventing the Shared Memory Protocol to be enabled.
Resolution: Manually enable the Shared Memory Protocol.
Open SQL Server Configuration Manager
Under “SQL Server Network Configuration” -> “Protocols for <Instance Name>” enable that Shared Memory Protocol.
Re-run the OutSystems Platform Community Edition installer.
*For detailed information about troubleshooting your installation please follow this links: how to start troubleshooting, log files, common error codes.