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Question:
Why when I try to instal SQL Server 2008 SP1 I get the following error message:
There are no SQL Server instances or shared features that can be updated on this computer.
Answer:
Make sure you are not trying to install SP1 onto a an unsupported version as in this case where SQL 2008 SP1 was being attempted to be applied on SQL 2008 R2.
Read the complete post at http://wmug.co.uk/blogs/cliffs_blog/archive/2010/09/23/faq-sql-2008-there-are-no-sql-server-instances-or-shared-features-that-can-be-updated-on-this-computer.aspx