Message type: E = Error
Message class:  HRPIQ00MBSS2 - Messages for Course Registration UI (Used only for Frontend) 
Message number: 001
Message text: Your Registration Cart is empty: No registration done
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 "HRPIQ00MBSS2001 Your Registration Cart is empty: No registration done" typically occurs in the context of SAP's Human Capital Management (HCM) module, particularly when dealing with the Employee Self-Service (ESS) or Manager Self-Service (MSS) functionalities related to course registrations or training events.
Cause: Empty Registration Cart: The most straightforward cause is that the user has not added any items (courses, events, etc.) to their registration cart before attempting to proceed with a registration. Session Timeout: If the user has been inactive for a while, their session may have timed out, leading to the cart being cleared. Technical Issues: There may be issues with the backend system or configuration that prevent items from being added to the cart. Authorization Issues: The user may not have the necessary permissions to register for courses or events, which could lead to an empty cart. Data Integrity Issues: There may be issues with the data related to the
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