Message type: E = Error
Message class:  TXRG_POSTING - Tax Register Posting Message Class 
Message number: 264
Message text: Exchange Rate type is empty
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The SAP error message TXRG_POSTING264 indicates that the exchange rate type is empty when trying to post a transaction that involves currency conversion. This error typically occurs in financial transactions where currency exchange rates are required for proper posting.
Cause: Missing Exchange Rate Type: The exchange rate type is not specified in the transaction or configuration.
Configuration Issues: The exchange rate type may not be defined in the system or may not be properly configured for the currencies involved. Transaction Data: The transaction data being posted may not include the necessary information regarding the exchange rate type.
Solution: Specify Exchange Rate Type: Ensure that the exchange rate type is specified in the transaction. This can often be done in the transaction screen where you enter the financial data. Check Configuration: Go to the SAP configuration settings (transaction code SPRO) and navigate to: Financial Accounting (FI) > Financial Accounting Global Settings > Currencies > Define Exchange Rate Types. Ensure that the exchange
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