You can join the Windows 10 Insider Program without a Microsoft Account (unofficially)

The Windows 10 Insider program has a few requirements but the most important ones are that users need to use a Microsoft Account to receive Insider builds and that data collecting needs to be set to full on the device. Offline Insider Enroll is a command line script that enrolls Windows 10 devices in the Insider program even if no Microsoft Account is used. The requirement to set Telemetry to full is not changed, however. You may check the state by using Windows-I to open the Settings application and going to Privacy > Diagnostics & feedback. There you need to… [Continue Reading]