Message type: E = Error
Message class:  /SAPAPO/OE -  
Message number: 021
Message text: Data was saved successfully
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.
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The SAP error message /SAPAPO/OE021 indicates that data was saved successfully in the context of Advanced Planning and Optimization (APO) within SAP. This message is not an error in the traditional sense; rather, it is an informational message that confirms that the operation you performed (such as saving a planning book, order, or other data) was completed successfully.
Cause: The message is triggered after a successful save operation in the APO system. It serves as a confirmation that the data you intended to save has been processed and stored correctly.
Solution: Since this message indicates success, there is no action required to resolve an error. However, if you are expecting a different outcome or if you are not seeing the expected results after this message, consider the following steps: Verify Data: Check the data you saved to ensure it reflects the changes you intended. Review Logs: Look at any relevant logs or messages in the system
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