How to lock specific users out of certain transactions
Not every user needs access to every transaction. Find out how to block certain users from specific transactions.
The only way to lock a specific transaction from a specific user is to not assign him the transaction code in the authorization profile of the user.
Please note that there is a way to lock a transaction code via Tcode SM01, but this is a system-wide activity and will lock the Tcode in the entire system.