Hi,
For desktop OSes (win7/8/8.1/10), only one user/session is allowed to be active (either local or remote). When another user try to login, the current user will be disconnected (not logoff).
While for server OSes (server 2008r2/2012/2012r2/2016/2019), by default, two users are allowed to login simultaneously (active sessions, either local or remote), if we want to more active sessions, we may buy RDP license, enable RDS role in the server to let multiple users to login simultaneously. For desktop OSes, there is no official way to allow multiple active sessions, that is, multiple sessions are allowed, however, only one session is active.
Hope the above clarifies.
Alex
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