I'm trying to install SQL Compact 3.5 SP2 after I've installed SQL 2012 RC0, on a x64 Windows 7. The x86 installer goes through fine. The x64 installer fails, with the error: "Error 25543.Failed to save changes to XML file c:\Windows\Microsoft.NET\Framework64\v4.0.30319\CONFIG\machine.config, system error: -2147024864" Note the \CONFIG (double backslash) where there should be a single backslash... any ideas why this is happening and how to solve it?