Getting Started with SQL Server 2008 R2 - Microsoft SQL Server 2008 R2 Administration - page 8

The following are some of the additional checks that SCC performs to determine if the SQL
Server editions in an in-place upgrade path are valid:
F Checks the system databases for features that are not supported in the SQL Server
edition to which you are upgrading
F Checks that neither SQL Server 7.0 nor SQL Server 7.0 OLAP Services is installed on
the server
SQL Server 2008 or higher versions are not supported on the server that has SQL Server 7.0.
F Checks all user databases for features that are not supported by the SQL
Server edition
F Checks if the SQL Server service can be restarted
F Checks that the SQL Server service is not set to Disabled
F Checks if the selected instance of SQL Server meets the upgrade matrix
requirements
F Checks if SQL Server Analysis Services is being upgraded to a valid edition
F SCC checks if the edition of the selected instance of SQL Server is supported for
'Allowable Upgrade Paths'
There's more...
As the prerequisite process of Slipstream is completed, we need to ensure that the installation
of SQL Server 2008 R2, Service Pack, and Hotfixes patches are applied with the setup steps.
To confirm the workflow process is followed correctly from the folder SQL2K8R2_FullSP ,
double-click on setup.exe file to continue the installation of RTM version, Service Pack, and
required hotfix patches.
While continuing the setup at the Installation Rules screen, the SCC rule checks for Update
Setup Media Language Compatibility value, which should be passed in order to proceed, as
shown in the following screenshot: