Use LazyWrite to specify how keys are written to the registry. LazyWrite is initialized to true when a registry object is first created. When LazyWrite is true, keys are written to the registry when they are closed, but the CloseKey procedure may return before the write operation takes place. 

When LazyWrite is false, keys are written to the registry before CloseKey returns. Set LazyWrite to false only when absolutely necessary. Setting LazyWrite to false guarantees that the changes an application makes to keys are written to the registry before further application processing takes place, but it uses more system resources when keys are closed. If LazyWrite is false, and an application is displaying or changing many registry entries, there will be a degradation in application performance. 

CloseKey