When trying to launch the SQL Configuration Manager, you receive the error:
"Cannot connect to WMI provider. You do not have permission or the server is unreachable."
SQL Configuration Manager error
You have multiple SQL instances installed on the machine and have uninstalled one of these instances. This problem occurs because the WMI provider is removed when you uninstall an instance of SQL Server 2008. As the 32-bit instance and the 64-bit instance of SQL Server 2008 share the same WMI configuration file, you will receive the above error if you uninstall one of the instances.
This is a known issue and can be resolved by following the Microsoft Support article: