According to Neowin, Microsoft has killed the final method for activating Windows without an internet connection—that is, activation by telephone. It appears to have been discontinued a few days ago.

Microsoft has seemingly disabled phone call activation for Windows 11, and perhaps older versions as well, making it impossible to activate Windows without an Internet connection. This is an unwelcome ...

Customers have noticed Microsoft's phone lines aren't supporting Windows phone activation anymore Support documentation still indicates it's possible despite ongoing struggles Looks like you now need ...

Microsoft has officially retired the traditional phone-based activation system for Windows and Office that served as a reliable fallback for users for over two decades. Indeed, the "slui 4" command ...