Message type: E = Error
Message class:  CUMTX - Variant Configuration - Master Data Maintenance 
Message number: 661
Message text: Upload not possible
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 CUMTX661, which states "Upload not possible," typically occurs during data uploads in SAP systems, particularly when using tools like LSMW (Legacy System Migration Workbench) or other data upload methods. This error can arise due to various reasons, and understanding the cause is essential for finding a solution. Causes of CUMTX661 Error File Format Issues: The file being uploaded may not be in the correct format or may contain invalid data. Data Structure Mismatch: The structure of the data in the upload file may not match the expected structure in SAP. Authorization Issues: The user may not have the necessary authorizations to perform the upload. Technical Settings: There may be technical settings or configurations in the SAP system that prevent the upload. Data Volume: The volume of data being uploaded may exceed system limits or performance thresholds. System Locking: The system may be locked for maintenance or other reasons, preventing uploads. Solutions to CUMTX661 Error Check
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