Message type: E = Error
Message class:  AR - SSRV function module messages 
Message number: 603
Message text: Invalid company registration number (CRN)
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The SAP error message AR603 "Invalid company registration number (CRN)" typically occurs when there is an issue with the company registration number entered in the system. This error can arise in various contexts, such as during the creation or modification of vendor or customer master data, or when processing transactions that require a valid CRN. Causes: Incorrect Format: The CRN may not conform to the expected format defined in the system. Different countries have different formats for CRNs. Missing CRN: The CRN field may be left blank when it is required. Invalid Characters: The CRN may contain invalid characters or symbols that are not allowed. Data Entry Errors: Typographical errors during data entry can lead to an invalid CRN.
Configuration Issues: The system may not be properly configured to recognize valid CRNs for the specific country or region. Outdated Information: The CRN may refer to a company that has been dissolved or is no longer valid. Solutions: Verify the
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