How to block a user id being logging in for more than twice?  i.e. I must restrict the user to be logged in at a time not more than twice (Not sessions, Loggins only).

Set the parameter in RZ10.

login/multi_login_users             = set to 1 to activate 

login/disable_multi_gui_login    = you can put a list of users that should be allow to logon multiple times

List the user IDs separated by commas ",".

Do not leave space characters between user IDs.

Restart the R/3 instance to see the changes.

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