In the Installation Rules of SQL Server 2012 RC0 setup, you may get the following:


It says:
This computer does not have the Microsoft .Net Framerwork 3.5 Service Pack 1 installed. If the operating system is Windows Vista or Windows Server 2008, download and install Microsoft .Net Framework 3.5 SP1 from …
No need to do this if running Windows Server 2008 R2 sp1; simply go to Server Manager >> Features >> Add Features, and click on the .Net Framework 3.5.1 Features link.

You also get this:

Click through without adding anything else, and continue the install. No need to back out and start over again.

Now hit the Re-run button, and your install is once again blingin!

Thanks,
Lee
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