Message type: E = Error
Message class:  CNV_10020 - Message class for package 10020 
Message number: 133
Message text: Select exactly one row
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The SAP error message CNV_10020133: Select exactly one row typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that the system expected the user to select a single row from a list of entries, but either no rows or multiple rows were selected instead.
Cause: Multiple Selections: The user may have selected more than one row in a table or list where only one selection is allowed. No Selection: The user may not have selected any row at all. Data Integrity Issues: There may be issues with the data being processed, leading to unexpected results in the selection. User Interface Issues: Sometimes, the user interface may not behave as expected, leading to confusion about what is selectable.
Solution: Select a Single Row: Ensure that you are selecting exactly one row from the list. If you have selected multiple rows, deselect them and
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