How To Fix /PF1/MSG_CONV_XML156 - Only one occurrence of '&' is allowed

SAP Error Message - Details

• Message type: E = Error

• Message class: /PF1/MSG_CONV_XML -

• Message number: 156

• Message text: Only one occurrence of '&' is allowed

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /PF1/MSG_CONV_XML156 - Only one occurrence of '&' is allowed ?

  The SAP error message /PF1/MSG_CONV_XML156: Only one occurrence of '&' is allowed typically occurs when there is an issue with the XML data being processed. This error indicates that the XML parser has encountered an invalid character sequence, specifically the ampersand (&) character, which is not properly formatted according to XML standards.
  Cause:
  
  
  Improperly Formatted XML: The ampersand character (&) is a special character in XML. It is used to denote the beginning of an entity reference. If you want to include an actual ampersand in your XML data, it must be escaped as &. If there are multiple unescaped ampersands or if an ampersand is followed by invalid characters, the parser will throw this error.
  
  
  Data Source Issues: The data being converted to XML may contain raw text that includes ampersands without proper escaping.
  
  
  Configuration Issues: There may be issues in the configuration of the XML generation process, leading to improper handling of special characters.
  
  
  Solution:
  
  
  Check and Escape Ampersands: Review the XML data being processed and ensure that all occurrences of the ampersand are properly escaped as &. This includes any data that is being dynamically generated or pulled from databases.
  
  
  Validate XML Structure: Use an XML validator to check the structure of your XML data. This can help identify any other formatting issues that may be present.
  
  
  Modify Data Source: If the data source is under your control, modify it to ensure that any ampersands are escaped before they are included in the XML output.
  
  
  Review Code Logic: If you are generating XML programmatically, review the code to ensure that it correctly handles special characters. Use libraries or functions that automatically escape special characters when generating XML.
  
  
  Test with Sample Data: Create a small sample of the XML data that reproduces the error and test it in isolation. This can help you pinpoint the exact cause of the issue.
  
  
  Related Information:
  
  
  XML Character Escaping: In XML, certain characters must be escaped to ensure that the document is well-formed. The most common characters that need to be escaped are:
  
  & as &
  < as &lt;
  > as &gt;
  " as &quot;
  ' as &apos;
  
  
  
  SAP Documentation: Refer to SAP's official documentation or support notes for more information on handling XML data and common error messages related to XML processing.
  
  
  Debugging Tools: Utilize debugging tools within SAP to trace the XML generation process and identify where the invalid characters are being introduced.
  
  
  By following these steps, you should be able to resolve the error and ensure that your XML data is correctly formatted.