Message type: E = Error
Message class:  CNV_PE_TB - PE Task Board Messages 
Message number: 004
Message text: Error assigning predecessors to task &1 for object &2 (subobject &3)
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The SAP error message CNV_PE_TB004 typically occurs during the execution of a conversion or migration process, particularly when dealing with task assignments in a project or data migration scenario. This error indicates that there is an issue with assigning predecessor tasks to a specific task for a given object and subobject.
Cause: The error can be caused by several factors, including: Missing Predecessor Tasks: The predecessor tasks that are supposed to be assigned to the specified task may not exist or may not be correctly defined in the system. Incorrect Object/Subobject: The object or subobject specified in the error message may not be valid or may not correspond to the expected configuration in the system. Data Integrity Issues: There may be inconsistencies or integrity issues in the data that prevent the assignment of predecessors.
Configuration Issues: There may be configuration settings in the project or migration tool that are not set up correctly, leading to this
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