Upgrade phone MS840 from Windows 8.1 to 10

[Windows Central Question]

How should I upgrade my Microsoft 540 phone to Windows 10 version from 8.1.
It was promised in advertisement it will be free.
If possible tell me procedure.

 

[colinkiama]

How should I upgrade my Microsoft 540 phone to Windows 10 version from 8.1.


It was promised in advertisement it will be free.


If possible tell me procedure.

It's not out yet for Phones. Wait till around November.