This guide can help you enable FILESTREAM, a necassary feature for CostOS.
CostOS Server installer usually can perform these steps but if you have different machines hosting SQL Server and CostOS database or not enough privileges for SQL assigned user, the following steps have to be done instead.
On the Start menu, point to All Programs, point to SQL Server 2014, point to Configuration Tools, and then click SQL Server Configuration Manager (if you cant find it just search for SQLServerManager12.msc).
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