TS Server Admins -
If your users have problems in reconnecting to a Terminal Service session after a connection drop or intentional disconnect, try the following support article:
What this does is add a value to the registry that changes the KeepAlive behavior. It stops the keep alive function after 1 minute so that the session will transition into a disconnect state. Once in the disconnect state, the session can be reconnected by the user. Without this value, the session may remain in an active state (depending on how the disconnect occured) and therefore the user cannot reconnect to it. Instead, the user may get a new session.