This setting allows you to disable multiple logins for a user, meaning that they can’t be logged in from more than one place or have more than one session at the same time.
If the user account is already in use, and a second login takes place, the first login will be disconnected immediately. We do this instead of preventing the second login to prevent an inactive browser left open, or user who closed their browser without logging out from accidentally locking themselves out of their own account.
When this setting is disabled, set to NO, a single user account can have as many active sessions as they want.
The main use case for preventing simultaneous logins is to deter account sharing – many people using a single, paid account.
By enabling this setting, you’re making account sharing almost pointless as if someone else logs in then the current user’s session will be closed (they’ll be logged out). Account sharing may still be possible, but it’ll become more difficult.
You can increase security by using this feature in conjunction with the Maximum Login IPs setting located beneath the toggle switch.
The “Maximum Login IPs” defines the number of different IP addresses that a user can log in from within a certain period of time controlled by the other setting just below it “Maximum Login Window (Hours)”.
Using all three settings in combination prevents members from sharing accounts in both private and corporate environments.