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3394922 - Understanding and resolving 'NIEROUT_SERV_UNKNOWN' issues in SAProuter


Errors with the code NIEROUT_SERV_UNKNOWN (rc=-91) are observed in the SAProuter log file. A typical error message appears as follows:

*** ERROR => NiBufIProcMsg: hdl 14 received rc=-91 (NIEROUT_SERV_UNKNOWN) from peer [nibuf.cpp 2025]



  • Operating System independent
  • Database independent
  • SAP NetWeaver
  • SAP Web Application Server for SAP S/4HANA
  • SAP ABAP Platform 


ABAP platform all versions ; SAP NetWeaver all versions ; SAP Web Application Server for SAP S/4HANA all versions


NIEROUT_SERV_UNKNOWN, saprouter, NiBufIProcMsg, connection, network connectivity, router string, name resolution , KBA , BC-CST-NI , Network Interface , BC-CST , Client/Server Technology , BC-NET , Formerly used for network tests , Problem

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