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I have several SQL Server 2008 R2 setup discs, but they're not labelled with which edition (Standard, Developer, Enterprise etc.) they are for.
Running them doesn't give much help as it just shows that it's a SQL Server 2008 R2 install, nothing more specific (unless I'm looking in the wrong place).
I hope that one of you smart cookies will be able to point me in the right direction to find out the edition of SQL Server on the discs.