How To Fix HTTP_HEADER001 - &1 entries found, &2 duplicate entries not shown

SAP Error Message - Details

• Message type: E = Error

• Message class: HTTP_HEADER - HTTP Header Framework

• Message number: 001

• Message text: &1 entries found, &2 duplicate entries not shown

Self-Explanatory Message

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.

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Smart SAP Assistant

• What is the cause and solution for SAP error message HTTP_HEADER001 - &1 entries found, &2 duplicate entries not shown ?

  The SAP error message HTTP_HEADER001 indicates that there are duplicate entries in the HTTP header of a request. This can occur in various scenarios, such as when making HTTP calls from SAP systems to external services or APIs. The message typically states that a certain number of entries were found, but some duplicate entries were not shown.
  Cause:
  
  Duplicate Headers: The most common cause of this error is that the HTTP request being sent contains duplicate header fields. For example, if the same header (like Authorization, Content-Type, etc.) is included multiple times, it can trigger this error.
  Configuration Issues: Sometimes, the configuration of the HTTP client or the way headers are being set in the code can lead to duplicates.
  Middleware or Proxy Issues: If there is middleware or a proxy server involved in the communication, it might be adding headers that are already present in the request.
  
  Solution:
  
  Check HTTP Headers: Review the code or configuration where the HTTP request is being constructed. Ensure that headers are not being added multiple times. You can log the headers before sending the request to identify duplicates.
  Remove Duplicates: If you find duplicate headers, modify the code to ensure that each header is only added once.
  Use Debugging Tools: Utilize debugging tools or transaction codes (like SICF for HTTP services) to trace the HTTP request and see the headers being sent.
  Review Middleware/Proxy Settings: If applicable, check the settings of any middleware or proxy servers to ensure they are not adding duplicate headers.
  SAP Notes: Check for any relevant SAP Notes that might address this issue, as there may be patches or updates that resolve specific cases of this error.
  
  Related Information:
  
  SAP Documentation: Refer to the official SAP documentation for the specific module or function you are working with to understand how HTTP requests are handled.
  Transaction Codes: Use transaction codes like SICF (for HTTP services) or SMICM (for Internet Communication Manager) to monitor and manage HTTP connections.
  Community Forums: Check SAP Community forums or other technical forums for similar issues and solutions shared by other users.
  
  By following these steps, you should be able to identify and resolve the cause of the HTTP_HEADER001 error in your SAP system.