Message type: E = Error
Message class:  FBS_SE - Messages for Transfer of FIN-MDM Data 
Message number: 123
Message text: Serious system error occurred (&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.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
Unfortunately, there isn't any extra information in this error notice.
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The SAP error message FBS_SE123, which indicates a "Serious system error occurred (&1)," typically points to a critical issue within the SAP system that requires immediate attention. This error can arise from various underlying causes, including but not limited to: Causes: System
Configuration Issues: Incorrect or incomplete configuration settings in the SAP system can lead to serious errors. Database Issues: Problems with the database, such as corruption or connectivity issues, can trigger this error. Program Errors: Bugs or issues in custom ABAP programs or standard SAP programs can cause unexpected behavior. Memory Issues: Insufficient memory allocation or resource constraints on the application server can lead to system errors. Transport Issues: Problems during the transport of changes from one system to another can result in inconsistencies. Kernel or Patch Issues: Outdated or incompatible kernel versions or patches can lead to system instability. Solutions: Check System Logs: Review the system logs (transaction SM21) and short dump analysis (transaction ST22) for more
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