SQL Server service accounts are virtual accounts as MSSQL$InstanceName.
When a SQL Server instance uses a directory to write data it is necessary that the virtual account has permissions to write in the directory.
Nevertheless, I have a server in which an instance is using a directory without, apparently, having the required permissions on it.
There are two groups with full permissions: Administrators and System. But the virtual account doesn't appear in the list.
How is it possible that the virtual service account writes in the directory? Is a virtual account able to write in any directory in the server?