Message type: E = Error
Message class:  U6 - Message Class for BRE 
Message number: 168
Message text: Enter an identification for every selected criterion
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 U6168, which states "Enter an identification for every selected criterion," typically occurs when you are trying to execute a report or transaction that requires specific criteria to be defined, but one or more of those criteria have not been properly filled out.
Cause: The error is usually caused by: Missing Input: You have selected certain criteria (like filters or parameters) but have not provided the necessary identification or value for one or more of those criteria. Incorrect Configuration: The selection screen may be configured in such a way that it expects certain mandatory fields to be filled out, and they are currently empty. User Input Error: Sometimes, it could be a simple oversight where the user has missed entering a value in a required field.
Solution: To resolve the U6168 error, you can take the following steps: Review Selected Criteria: Go back to the selection screen and carefully review all the criteria you have
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