Yesterday I spent 4 hours trying to install SQL Server on my newly installed Windows 8, and I kept receiving the same error: ” is not a valid login or you don’t have permission.
At first when I started the installation of SQL Server, it did complain about compatibility issues, but I chose to ignore it as I thought it might have to do with the fact it might not have properly mounted my ISO image of the SQL Server.
And just when I was about to reinstall Windows after trying on several things I came across the solution to fix this: my computer name and the username are the same. This interferes with the Windows Authentication for SQL Server. My username on Windows 8 was Olia\Olia.
After changing my computer name to Olia-PC I’ve reinstalled the SQL Server and it worked like a charm.