Message type: E = Error
Message class:  ATO_CUSTOMER - ATO Messages for the End User 
Message number: 836
Message text: All changes locked by user &1.
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message ATO_CUSTOMER836, which states "All changes locked by user &1," typically indicates that a user has locked the object or data you are trying to modify. This can happen in various scenarios, such as when a user is currently editing a record or has not properly released a lock after completing their work.
Cause: User Lock: The user identified by &1 has an active lock on the object you are trying to change. This could be due to: The user is currently editing the object. The user has not released the lock after completing their changes. A previous session did not close properly, leaving the lock active. System Lock: Sometimes, system-level locks can occur due to background jobs or processes that are running and have not yet completed.
Solution: Identify the Locking User: Use transaction code SM12 to view the locks in the system. You can filter by the user ID to see what objects
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