We have a SQL Server 2012 installation with the file share feature enabled. We then have an IIS application that can write directly to the \localhost\MSSQLServer... share that the database creates.
The problem I have is that to get this to work, I have had to create a new user account and set that as the app pool identity for the application and then add this user to SQL Server and finally give that user the sysadmin role. If I give it any other server role, it doesn't get write access to the share.
Having an IIS app pool user account have unrestricted access to the entire SQL Server isn't ideal. Is there a way therefore to configure SQL Server to allow a lower-privilege role access to the file share?