Windows 10 Anniversary Update: Cortana has 'absolutely no way of identifying you' if you log out of it, says Microsoft

System log-in and Cortana log-in are totally different things, promises company

Windows 10 Anniversary Update won't let you disable Cortana, but Microsoft has confirmed that logging out of the 'personal assistant' will stop it logging voice and keystrokes.

The confirmation came from Microsoft's head of Windows consumer marketing, Rob Epstein, while he delivered a Windows 10 Anniversary Update demonstration to Computing. We asked Epstein why Cortana now has to be active all the time - whereas in vanilla Windows 10 it can be entirely disabled - and if this affects the amount of data it collects.

"Cortana is core to the search experience," said Epstein.

"Cortana is used to search the machine, and to search the web. I don't need to log in - so I can use it completely anonymously - and therefore I won't get many of the benefits of sharing that data, but it will still provide basic functionality."

Adding he'd need to "confirm with the product team" (a confirmation we're still waiting for), Epstein offered clarification:

"If you have not logged in [to Cortana], other than the fact everything is completely anonymised anyway, there's absolutely no way of identifying any of your key strokes in any way that would be tied back to you."

From using Windows 10 Anniversary Update ourselves, Computing can confirm a user can log in and log out of Cortana separately, but we pushed Epstein to explain how the "logging in" around Cortana works when compared to the central, core system log-in most users will provide Windows 10 when signing in with an active email account, such as an Outlook or Hotmail account:

"You'd typically use your same Hotmail account to log in, but you do need to choose to log Cortana in separately or not. So therefore you can be logged into the system without Cortana being able to take any voice and say, 'Oh, we know it's that user or who those keystrokes [belong to]."

Epstein added that Microsoft is generally "very clear that we don't use things like your searches for ad feeding.

"If you happen to do a web search then you'll get ads based on that search the same as any web search, etc. We are very open with our privacy policies - we've added a whole privacy section to the Microsoft website, which makes it very clear and transparent."

Computing also asked Epstein why Microsoft feels the need to re-brand what - when not logged in - should essentially be just the rudimentary Windows search function that spans back decades.

"From a business perspective, we have Cortana Analytics, which is effectively a brand wrapper onto some very sophisticated AI capabilities and big data, which is something Satya [Nadella] has led us through, and sees it's going to be the future, and that's exposing itself in all sorts of ways companies are finding useful," said Epstein. Which didn't exactly answer our question.

"But everything with Cortana is selectable by exactly what information you choose to share or not - we're open with that information," he insisted.