How To Fix /IWBEP/CM_MGW_RT181 - Is-Not-Modified is not allowed in case If-Modified-Since is initial

/IWBEP/CM_MGW_RT181 - Overview

• Message type: E = Error

• Message class: /IWBEP/CM_MGW_RT -

• Message number: 181

• Message text: Is-Not-Modified is not allowed in case If-Modified-Since is initial

Self-Explanatory Message

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/IWBEP/CM_MGW_RT181 - Details

• The SAP error message /IWBEP/CM_MGW_RT181 with the description "Is-Not-Modified is not allowed in case If-Modified-Since is initial" typically occurs in the context of OData services when there is an issue with the handling of HTTP conditional requests. This error is related to the use of the If-Modified-Since HTTP header in requests to the OData service.
  
  Cause:
  The error arises when a client sends a request to the OData service with the If-Modified-Since header not set (i.e., it is empty or initial), but the server is trying to respond with a 304 Not Modified status. The 304 Not Modified response indicates that the resource has not changed since the specified date in the If-Modified-Since header. If this header is not provided, the server cannot determine whether to return a 304 response or the full resource representation.
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Check Client Request: Ensure that the client making the