If you receive the error "Cannot connect to WMI provider. You do not have permission or the server is unreachable." when attempting to launch the SQL Configuration Manager:
You may have multiple SQL instances installed on the machine and have uninstalled one of these instances. This issue occurs when you uninstall an instance of SQL Server 2008 because the 32- and 64-bit instances share the same WMI. When you uninstall one of the instances, the WMI provider is removed.
To resolve this issue, refer to the Microsoft Support article Error message when you open SQL Server Configuration Manager in SQL Server: "Cannot connect to WMI provider. You do not have permission or the server is unreachable".