Message type: E = Error
Message class:  TXRG_POSTING - Tax Register Posting Message Class 
Message number: 605
Message text: Tax Type is empty
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The SAP error message TXRG_POSTING605 indicates that there is an issue with the tax type being empty during a posting process. This error typically occurs in the context of financial transactions where tax information is required but not provided.
Cause: Missing Tax Type Configuration: The tax type may not be defined in the system for the specific transaction or document type. Incorrect Master Data: The master data for the customer, vendor, or material may not have the necessary tax information configured. Transaction Type: The transaction type being used may not be set up to handle tax correctly. Custom Code or Enhancements: If there are custom developments or enhancements in the system, they may not be handling tax types properly.
Solution: Check Tax Configuration: Go to the transaction code OBYZ (for tax codes) and ensure that the relevant tax types are configured correctly. Verify that the tax codes are assigned to the appropriate tax types. Review Master Data: Check the master data
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