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Message type: E = Error
Message class: ATO_CUSTOMER - ATO Messages for the End User
Message number: 256
Message text: Prefix &1 not allowed. Choose a prefix that starts with Z or Y.
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.
Unfortunately, there isn't any extra information in this error notice.
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The SAP error message ATO_CUSTOMER256 indicates that a specific prefix used in a transaction or configuration does not meet the system's requirements. In this case, the prefix must start with either "Z" or "Y". This is a common restriction in SAP systems, as "Z" and "Y" prefixes are typically reserved for custom developments or user-defined objects, while other prefixes are reserved for standard SAP objects.
Cause:
- Invalid Prefix: The prefix you are trying to use does not start with "Z" or "Y".
- Configuration Error: The system is configured to only accept certain prefixes for custom objects, and the one you are using does not comply with this rule.
Solution:
Change the Prefix: Modify the prefix of the object or transaction you are trying to create or use. Ensure that it starts with "Z" or "Y".
- For example, if you were trying to use a prefix like "A123", change it to "Z123" or "Y123".
Check Configuration: If you are unsure about the allowed prefixes, consult with your SAP administrator or check the system configuration to understand the naming conventions in place.
Review Documentation: If you are developing custom objects, refer to your organization's development guidelines to ensure compliance with naming conventions.
Related Information:
If you continue to encounter issues after making these changes, consider reaching out to your SAP support team for further assistance.
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SAP messages fall into 3 different categories: Error messages
(message type = E), Warnings (W) or Informational (I) messages.
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