SAP Knowledge Base Article - Preview

2465530 - TNS-12518: TNS:listener could not hand off client connection


  • You cannot connect to the database
  • When you try to connect, the system hangs
  • Restarting the listener doesn't resolve the problem
  • Restarting the database resolves it temporarily, but after a while the issue happens again
  • Listener.log file shows the following messages for the connection attempts:
"TNS-12518: TNS:listener could not hand off client connection
 TNS-12560: TNS:protocol adapter error
  TNS-00530: Protocol adapter error
   64-bit Windows Error: 258: Unknown error"



  • SAP Systems based on SAP NetWeaver
  • Windows operating system
  • Oracle database


SAP NetWeaver all versions


ora, tns, 12518, 12560, 530, tns-530, cannot, connect, can't, cant, listener, hanging, freezing, freezes , KBA , BC-DB-ORA , Oracle , BC-DB-ORA-DBA , Database Administration , Problem

About this page

This is a preview of a SAP Knowledge Base Article. Click more to access the full version on SAP for Me (Login required).

Search for additional results

Visit SAP Support Portal's SAP Notes and KBA Search.