Microsoft has decided to roll back their decision to add CCleaner to a blacklist that would prevent the software’s official site, www.ccleaner.com, from being posted in the Microsoft Community Forums. Microsoft has long held the position that they do not support Windows Registry cleaners or system optimizers as they have a history of causing issues for those who run them and many can be considered scams. Microsoft is not responsible for issues caused by using a registry cleaning utility. We strongly recommend that you only change values in the registry that you understand or have been instructed to change.
Source: https://www.bleepingcomputer.com/news/microsoft/microsoft-removes-ccleaner-ban-from-their-community-forums/