I'm preparing for my first SBS2003 to SBS2008 migration so plouighing through all of the suggested documentation according to Microsoft. Part of the preparatory work is to establish a Domain Administrators login on the source (SBS2003) server, no probs. But the following has me confused, it states in http://technet.microsoft.com/en-us/library/cc527566(WS.10).aspx
"This account must be a member of the Domain Admins, Enterprise Admins, and Schema Admins groups. However, the default security group for the account cannot be one of these three groups."
Does an account have a default security group and how do you tell which group is the default. I feel as though I'm being thick but I don't want to start this process with any misunderstanding so can anyone help out here.