You receive this error when you attempt to login via Microsoft SQL Server Management Studio
I was a member of the Domain Admins group and had sysadmin access to the databases. The application log in the event viewer displays the following information
Reason: Token-based server access validation failed with an infrastructure error. Check for previous errors. [CLIENT: <local machine>]
This seems to be linked to UAC (User Account Control) and it being set high. Right clicking on MS SQL SMS and logging on as Administrator resolves this!