"5. Unable to install SQL Server 2008 SP1
“The version of SQL Server instance Shared Component does not match the version expected by the SQL Server update. The installed SQL Server product version is 10.50.1447.4, and the expected SQL Server version is 10.0.1600.22.
The error message: There are no SQL Server Instances or Shared Features that can be updated on this computer”
If you’re getting this error, chances are you are trying to apply service pack (SP1) AND you are using a version of SQL Server that is below the RTM (release to manufacturing) level."
SQL Server product version 10.50.xxxx.x refers to SQL Server 2008 R2 which is a different product than SQL Server 2008. Microsoft hasn't released SP1 for SQL Server 2008 R2 yet to my knowledge although SQL Server 2008 R2 Service Pack 1 Customer Technology Preview is now available.