In reply to Nigel Pain.

I suspect it's the installation process that's presenting the trouble. If SAS Enterprise Guide was already on the machine when the OS was upgraded to Windows 8, it would probably continue to work. There are no specific known runtime problems with Windows 8 and EG 5.1 -- it's just that when EG 5.1 was released, Windows 8 wasn't available for testing and therefore "certification" from SAS.

You might be able to workaround by installing all of the SAS Enterprise Guide prerequisites first -- the items in the System Requirements Wizard -- before installing EG. That includes the proper version of Microsoft .NET, MSVC runtimes, etc.