This operation can be performed only on a computer that is joined to a server farm by users who have permissions in SQL Server to read from the configuration database. To connect this server to the server farm, use the SharePoint Products Configuration Wizard, located on the Start menu in Microsoft SharePoint 2010 Products.
I came across with error when i going to restore the SharePoint site to another farm. in here i ran the application as “run as administrator”. the problem is we want to have permission to SharePoint database. so you can put your username to SharePoint SQL server database and give the sys admin permission.
or else you can use already configured user.
Same error occurred to me in another time. But this time i found All server in my farm do not connected to domain properly. You can figure that out by pinging.