Configuration system failed to initialize 0x84B10001.
Applies to: SQL Server 2008, SQL Server 2008 R2, Windows 7 64-bit, Windows Vista 
64-bit.
 
Problem Description.
 
While trying to install SQL Server 2008 R2 on a Windows 7 we received a popup 
message with the following error:
SQL Server Setup has encountered the following error:
Configuration system failed to initialize
Error code 0x84B10001.
 
Workaround.
The workaround provided is the following:
"C:\Windows\Microsoft.NET\Framework64\v2.0.50727\CONFIG\machine.config
The machine.config file had the <system.serviceModel> node, I reverted back to 
the machine.config.default file."
Source: Microsoft Connect item #381293 
(no longer exists).