Message type: E = Error
Message class:  RSO_RES_QMSGS - Messages directly related to Query Designer. 
Message number: 004
Message text: Could not retrieve lock list for user &1
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The SAP error message RSO_RES_QMSGS004 indicates that the system could not retrieve the lock list for a specific user. This error typically occurs in the context of SAP BW (Business Warehouse) or when dealing with queries and reporting.
Cause: User Locking Issues: The user may be locked in the system, preventing the retrieval of the lock list. Authorization Issues: The user may not have the necessary authorizations to access the lock list. System Performance: There may be performance issues or system overload that prevent the retrieval of the lock list. Database Issues: Problems with the underlying database or connectivity issues can also lead to this error. Temporary System Glitches: Sometimes, temporary issues in the SAP system can cause this error.
Solution: Check User Status: Verify if the user is locked in the system. You can do this by checking the user status in transaction SU01 (User Maintenance). Review Authorizations: Ensure that the user has the necessary authorizations to access
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