Message type: E = Error
Message class:  ATO_CUSTOMER - ATO Messages for the End User 
Message number: 809
Message text: You are about to import versions &1 to &2 of collection &3.
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The SAP error message ATO_CUSTOMER809 typically occurs in the context of the SAP Advanced Planning and Optimization (APO) module, particularly when dealing with the import of versions in a collection. This message indicates that there is an issue with the import process of the specified versions of a collection.
Cause: The error message ATO_CUSTOMER809 can be triggered by several factors, including: Version Conflicts: The versions you are trying to import may have conflicts with existing versions in the system. Data Integrity Issues: There may be issues with the data integrity of the versions being imported, such as missing or inconsistent data. Authorization Issues: The user may not have the necessary authorizations to perform the import operation. System Configuration: There may be configuration settings in the system that prevent the import of certain versions.
Solution: To resolve the ATO_CUSTOMER809 error, you can take the following steps: Check Version Compatibility: Ensure that the versions you are trying to import are compatible
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