Microsoft has finally responded to the privacy concerns of Windows 10 on its blog. Windows chief Terry Myerson claims that the data Windows 10 collects is encrypted in transit to their servers, and then stored in secure facilities. No matter what privacy options you choose, neither Windows 10 nor any other Microsoft software scans the content of your email or other communications, or your files, in order to deliver targeted advertising to you.
The data which Windows 10 collects helps the company to provide a secure and reliable experience. This includes data like an anonymous device ID, device type, and application crash data which Microsoft and our developer partners use to continuously improve application reliability. The new OS also collects Personalization Data for the new personal assistant service Cortana.