You can create a registry key that is available only in memory and that will not be persisted when the computer is restarted. This is known as a volatile key. You can specify that you want to create a volatile or non-volatile key by using the erload:Microsoft.Win32.RegistryKey.CreateSubKey method overloads that take an options parameter.
A non-volatile key. This is the default.
A volatile key. The information is stored in memory and is not preserved when the corresponding registry hive is unloaded.